drivers/media/dvb-frontends/nxt6000.c - arm/linux-arm-legacy - Git at Google

 /*
 	NxtWave Communications - NXT6000 demodulator driver

     Copyright (C) 2002-2003 Florian Schirmer <jolt@tuxbox.org>
     Copyright (C) 2003 Paul Andreassen <paul@andreassen.com.au>

     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 <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/slab.h>

 #include "dvb_frontend.h"
 #include "nxt6000_priv.h"
 #include "nxt6000.h"


 struct nxt6000_state {
 	struct i2c_adapter* i2c;
 	/* configuration settings */
 	const struct nxt6000_config* config;
 	struct dvb_frontend frontend;
 };

 static int debug;
 #define dprintk if (debug) printk

 static int nxt6000_writereg(struct nxt6000_state* state, u8 reg, u8 data)
 {
 	u8 buf[] = { reg, data };
 	struct i2c_msg msg = {.addr = state->config->demod_address,.flags = 0,.buf = buf,.len = 2 };
 	int ret;

 	if ((ret = i2c_transfer(state->i2c, &msg, 1)) != 1)
 		dprintk("nxt6000: nxt6000_write error (reg: 0x%02X, data: 0x%02X, ret: %d)\n", reg, data, ret);

 	return (ret != 1) ? -EIO : 0;
 }

 static u8 nxt6000_readreg(struct nxt6000_state* state, u8 reg)
 {
 	int ret;
 	u8 b0[] = { reg };
 	u8 b1[] = { 0 };
 	struct i2c_msg msgs[] = {
 		{.addr = state->config->demod_address,.flags = 0,.buf = b0,.len = 1},
 		{.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b1,.len = 1}
 	};

 	ret = i2c_transfer(state->i2c, msgs, 2);

 	if (ret != 2)
 		dprintk("nxt6000: nxt6000_read error (reg: 0x%02X, ret: %d)\n", reg, ret);

 	return b1[0];
 }

 static void nxt6000_reset(struct nxt6000_state* state)
 {
 	u8 val;

 	val = nxt6000_readreg(state, OFDM_COR_CTL);

 	nxt6000_writereg(state, OFDM_COR_CTL, val & ~COREACT);
 	nxt6000_writereg(state, OFDM_COR_CTL, val | COREACT);
 }

 static int nxt6000_set_bandwidth(struct nxt6000_state *state, u32 bandwidth)
 {
 	u16 nominal_rate;
 	int result;

 	switch (bandwidth) {
 	case 6000000:
 		nominal_rate = 0x55B7;
 		break;

 	case 7000000:
 		nominal_rate = 0x6400;
 		break;

 	case 8000000:
 		nominal_rate = 0x7249;
 		break;

 	default:
 		return -EINVAL;
 	}

 	if ((result = nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, nominal_rate & 0xFF)) < 0)
 		return result;

 	return nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, (nominal_rate >> 8) & 0xFF);
 }

 static int nxt6000_set_guard_interval(struct nxt6000_state* state, fe_guard_interval_t guard_interval)
 {
 	switch (guard_interval) {

 	case GUARD_INTERVAL_1_32:
 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x00 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

 	case GUARD_INTERVAL_1_16:
 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x01 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

 	case GUARD_INTERVAL_AUTO:
 	case GUARD_INTERVAL_1_8:
 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x02 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

 	case GUARD_INTERVAL_1_4:
 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x03 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

 	default:
 		return -EINVAL;
 	}
 }

 static int nxt6000_set_inversion(struct nxt6000_state* state, fe_spectral_inversion_t inversion)
 {
 	switch (inversion) {

 	case INVERSION_OFF:
 		return nxt6000_writereg(state, OFDM_ITB_CTL, 0x00);

 	case INVERSION_ON:
 		return nxt6000_writereg(state, OFDM_ITB_CTL, ITBINV);

 	default:
 		return -EINVAL;

 	}
 }

 static int nxt6000_set_transmission_mode(struct nxt6000_state* state, fe_transmit_mode_t transmission_mode)
 {
 	int result;

 	switch (transmission_mode) {

 	case TRANSMISSION_MODE_2K:
 		if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x00 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
 			return result;

 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x00 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

 	case TRANSMISSION_MODE_8K:
 	case TRANSMISSION_MODE_AUTO:
 		if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x02 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
 			return result;

 		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x01 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

 	default:
 		return -EINVAL;

 	}
 }

 static void nxt6000_setup(struct dvb_frontend* fe)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	nxt6000_writereg(state, RS_COR_SYNC_PARAM, SYNC_PARAM);
 	nxt6000_writereg(state, BER_CTRL, /*(1 << 2) | */ (0x01 << 1) | 0x01);
 	nxt6000_writereg(state, VIT_BERTIME_2, 0x00);  // BER Timer = 0x000200 * 256 = 131072 bits
 	nxt6000_writereg(state, VIT_BERTIME_1, 0x02);  //
 	nxt6000_writereg(state, VIT_BERTIME_0, 0x00);  //
 	nxt6000_writereg(state, VIT_COR_INTEN, 0x98); // Enable BER interrupts
 	nxt6000_writereg(state, VIT_COR_CTL, 0x82);   // Enable BER measurement
 	nxt6000_writereg(state, VIT_COR_CTL, VIT_COR_RESYNC | 0x02 );
 	nxt6000_writereg(state, OFDM_COR_CTL, (0x01 << 5) | (nxt6000_readreg(state, OFDM_COR_CTL) & 0x0F));
 	nxt6000_writereg(state, OFDM_COR_MODEGUARD, FORCEMODE8K | 0x02);
 	nxt6000_writereg(state, OFDM_AGC_CTL, AGCLAST | INITIAL_AGC_BW);
 	nxt6000_writereg(state, OFDM_ITB_FREQ_1, 0x06);
 	nxt6000_writereg(state, OFDM_ITB_FREQ_2, 0x31);
 	nxt6000_writereg(state, OFDM_CAS_CTL, (0x01 << 7) | (0x02 << 3) | 0x04);
 	nxt6000_writereg(state, CAS_FREQ, 0xBB);	/* CHECKME */
 	nxt6000_writereg(state, OFDM_SYR_CTL, 1 << 2);
 	nxt6000_writereg(state, OFDM_PPM_CTL_1, PPM256);
 	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, 0x49);
 	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, 0x72);
 	nxt6000_writereg(state, ANALOG_CONTROL_0, 1 << 5);
 	nxt6000_writereg(state, EN_DMD_RACQ, (1 << 7) | (3 << 4) | 2);
 	nxt6000_writereg(state, DIAG_CONFIG, TB_SET);

 	if (state->config->clock_inversion)
 		nxt6000_writereg(state, SUB_DIAG_MODE_SEL, CLKINVERSION);
 	else
 		nxt6000_writereg(state, SUB_DIAG_MODE_SEL, 0);

 	nxt6000_writereg(state, TS_FORMAT, 0);
 }

 static void nxt6000_dump_status(struct nxt6000_state *state)
 {
 	u8 val;

 /*
 	printk("RS_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, RS_COR_STAT));
 	printk("VIT_SYNC_STATUS: 0x%02X\n", nxt6000_readreg(fe, VIT_SYNC_STATUS));
 	printk("OFDM_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_COR_STAT));
 	printk("OFDM_SYR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_SYR_STAT));
 	printk("OFDM_TPS_RCVD_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_1));
 	printk("OFDM_TPS_RCVD_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_2));
 	printk("OFDM_TPS_RCVD_3: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_3));
 	printk("OFDM_TPS_RCVD_4: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_4));
 	printk("OFDM_TPS_RESERVED_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_1));
 	printk("OFDM_TPS_RESERVED_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_2));
 */
 	printk("NXT6000 status:");

 	val = nxt6000_readreg(state, RS_COR_STAT);

 	printk(" DATA DESCR LOCK: %d,", val & 0x01);
 	printk(" DATA SYNC LOCK: %d,", (val >> 1) & 0x01);

 	val = nxt6000_readreg(state, VIT_SYNC_STATUS);

 	printk(" VITERBI LOCK: %d,", (val >> 7) & 0x01);

 	switch ((val >> 4) & 0x07) {

 	case 0x00:
 		printk(" VITERBI CODERATE: 1/2,");
 		break;

 	case 0x01:
 		printk(" VITERBI CODERATE: 2/3,");
 		break;

 	case 0x02:
 		printk(" VITERBI CODERATE: 3/4,");
 		break;

 	case 0x03:
 		printk(" VITERBI CODERATE: 5/6,");
 		break;

 	case 0x04:
 		printk(" VITERBI CODERATE: 7/8,");
 		break;

 	default:
 		printk(" VITERBI CODERATE: Reserved,");

 	}

 	val = nxt6000_readreg(state, OFDM_COR_STAT);

 	printk(" CHCTrack: %d,", (val >> 7) & 0x01);
 	printk(" TPSLock: %d,", (val >> 6) & 0x01);
 	printk(" SYRLock: %d,", (val >> 5) & 0x01);
 	printk(" AGCLock: %d,", (val >> 4) & 0x01);

 	switch (val & 0x0F) {

 	case 0x00:
 		printk(" CoreState: IDLE,");
 		break;

 	case 0x02:
 		printk(" CoreState: WAIT_AGC,");
 		break;

 	case 0x03:
 		printk(" CoreState: WAIT_SYR,");
 		break;

 	case 0x04:
 		printk(" CoreState: WAIT_PPM,");
 		break;

 	case 0x01:
 		printk(" CoreState: WAIT_TRL,");
 		break;

 	case 0x05:
 		printk(" CoreState: WAIT_TPS,");
 		break;

 	case 0x06:
 		printk(" CoreState: MONITOR_TPS,");
 		break;

 	default:
 		printk(" CoreState: Reserved,");

 	}

 	val = nxt6000_readreg(state, OFDM_SYR_STAT);

 	printk(" SYRLock: %d,", (val >> 4) & 0x01);
 	printk(" SYRMode: %s,", (val >> 2) & 0x01 ? "8K" : "2K");

 	switch ((val >> 4) & 0x03) {

 	case 0x00:
 		printk(" SYRGuard: 1/32,");
 		break;

 	case 0x01:
 		printk(" SYRGuard: 1/16,");
 		break;

 	case 0x02:
 		printk(" SYRGuard: 1/8,");
 		break;

 	case 0x03:
 		printk(" SYRGuard: 1/4,");
 		break;
 	}

 	val = nxt6000_readreg(state, OFDM_TPS_RCVD_3);

 	switch ((val >> 4) & 0x07) {

 	case 0x00:
 		printk(" TPSLP: 1/2,");
 		break;

 	case 0x01:
 		printk(" TPSLP: 2/3,");
 		break;

 	case 0x02:
 		printk(" TPSLP: 3/4,");
 		break;

 	case 0x03:
 		printk(" TPSLP: 5/6,");
 		break;

 	case 0x04:
 		printk(" TPSLP: 7/8,");
 		break;

 	default:
 		printk(" TPSLP: Reserved,");

 	}

 	switch (val & 0x07) {

 	case 0x00:
 		printk(" TPSHP: 1/2,");
 		break;

 	case 0x01:
 		printk(" TPSHP: 2/3,");
 		break;

 	case 0x02:
 		printk(" TPSHP: 3/4,");
 		break;

 	case 0x03:
 		printk(" TPSHP: 5/6,");
 		break;

 	case 0x04:
 		printk(" TPSHP: 7/8,");
 		break;

 	default:
 		printk(" TPSHP: Reserved,");

 	}

 	val = nxt6000_readreg(state, OFDM_TPS_RCVD_4);

 	printk(" TPSMode: %s,", val & 0x01 ? "8K" : "2K");

 	switch ((val >> 4) & 0x03) {

 	case 0x00:
 		printk(" TPSGuard: 1/32,");
 		break;

 	case 0x01:
 		printk(" TPSGuard: 1/16,");
 		break;

 	case 0x02:
 		printk(" TPSGuard: 1/8,");
 		break;

 	case 0x03:
 		printk(" TPSGuard: 1/4,");
 		break;

 	}

 	/* Strange magic required to gain access to RF_AGC_STATUS */
 	nxt6000_readreg(state, RF_AGC_VAL_1);
 	val = nxt6000_readreg(state, RF_AGC_STATUS);
 	val = nxt6000_readreg(state, RF_AGC_STATUS);

 	printk(" RF AGC LOCK: %d,", (val >> 4) & 0x01);
 	printk("\n");
 }

 static int nxt6000_read_status(struct dvb_frontend* fe, fe_status_t* status)
 {
 	u8 core_status;
 	struct nxt6000_state* state = fe->demodulator_priv;

 	*status = 0;

 	core_status = nxt6000_readreg(state, OFDM_COR_STAT);

 	if (core_status & AGCLOCKED)
 		*status |= FE_HAS_SIGNAL;

 	if (nxt6000_readreg(state, OFDM_SYR_STAT) & GI14_SYR_LOCK)
 		*status |= FE_HAS_CARRIER;

 	if (nxt6000_readreg(state, VIT_SYNC_STATUS) & VITINSYNC)
 		*status |= FE_HAS_VITERBI;

 	if (nxt6000_readreg(state, RS_COR_STAT) & RSCORESTATUS)
 		*status |= FE_HAS_SYNC;

 	if ((core_status & TPSLOCKED) && (*status == (FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)))
 		*status |= FE_HAS_LOCK;

 	if (debug)
 		nxt6000_dump_status(state);

 	return 0;
 }

 static int nxt6000_init(struct dvb_frontend* fe)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	nxt6000_reset(state);
 	nxt6000_setup(fe);

 	return 0;
 }

 static int nxt6000_set_frontend(struct dvb_frontend *fe)
 {
 	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
 	struct nxt6000_state* state = fe->demodulator_priv;
 	int result;

 	if (fe->ops.tuner_ops.set_params) {
 		fe->ops.tuner_ops.set_params(fe);
 		if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 	}

 	result = nxt6000_set_bandwidth(state, p->bandwidth_hz);
 	if (result < 0)
 		return result;

 	result = nxt6000_set_guard_interval(state, p->guard_interval);
 	if (result < 0)
 		return result;

 	result = nxt6000_set_transmission_mode(state, p->transmission_mode);
 	if (result < 0)
 		return result;

 	result = nxt6000_set_inversion(state, p->inversion);
 	if (result < 0)
 		return result;

 	msleep(500);
 	return 0;
 }

 static void nxt6000_release(struct dvb_frontend* fe)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;
 	kfree(state);
 }

 static int nxt6000_read_snr(struct dvb_frontend* fe, u16* snr)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	*snr = nxt6000_readreg( state, OFDM_CHC_SNR) / 8;

 	return 0;
 }

 static int nxt6000_read_ber(struct dvb_frontend* fe, u32* ber)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18 );

 	*ber = (nxt6000_readreg( state, VIT_BER_1 ) << 8 ) |
 		nxt6000_readreg( state, VIT_BER_0 );

 	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18); // Clear BER Done interrupts

 	return 0;
 }

 static int nxt6000_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	*signal_strength = (short) (511 -
 		(nxt6000_readreg(state, AGC_GAIN_1) +
 		((nxt6000_readreg(state, AGC_GAIN_2) & 0x03) << 8)));

 	return 0;
 }

 static int nxt6000_fe_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings *tune)
 {
 	tune->min_delay_ms = 500;
 	return 0;
 }

 static int nxt6000_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 {
 	struct nxt6000_state* state = fe->demodulator_priv;

 	if (enable) {
 		return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x01);
 	} else {
 		return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x00);
 	}
 }

 static struct dvb_frontend_ops nxt6000_ops;

 struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config,
 				    struct i2c_adapter* i2c)
 {
 	struct nxt6000_state* state = NULL;

 	/* allocate memory for the internal state */
 	state = kzalloc(sizeof(struct nxt6000_state), GFP_KERNEL);
 	if (state == NULL) goto error;

 	/* setup the state */
 	state->config = config;
 	state->i2c = i2c;

 	/* check if the demod is there */
 	if (nxt6000_readreg(state, OFDM_MSC_REV) != NXT6000ASICDEVICE) goto error;

 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &nxt6000_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;

 error:
 	kfree(state);
 	return NULL;
 }

 static struct dvb_frontend_ops nxt6000_ops = {
 	.delsys = { SYS_DVBT },
 	.info = {
 		.name = "NxtWave NXT6000 DVB-T",
 		.frequency_min = 0,
 		.frequency_max = 863250000,
 		.frequency_stepsize = 62500,
 		/*.frequency_tolerance = *//* FIXME: 12% of SR */
 		.symbol_rate_min = 0,	/* FIXME */
 		.symbol_rate_max = 9360000,	/* FIXME */
 		.symbol_rate_tolerance = 4000,
 		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 			FE_CAN_FEC_4_5 | FE_CAN_FEC_5_6 | FE_CAN_FEC_6_7 |
 			FE_CAN_FEC_7_8 | FE_CAN_FEC_8_9 | FE_CAN_FEC_AUTO |
 			FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
 			FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
 			FE_CAN_HIERARCHY_AUTO,
 	},

 	.release = nxt6000_release,

 	.init = nxt6000_init,
 	.i2c_gate_ctrl = nxt6000_i2c_gate_ctrl,

 	.get_tune_settings = nxt6000_fe_get_tune_settings,

 	.set_frontend = nxt6000_set_frontend,

 	.read_status = nxt6000_read_status,
 	.read_ber = nxt6000_read_ber,
 	.read_signal_strength = nxt6000_read_signal_strength,
 	.read_snr = nxt6000_read_snr,
 };

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

 MODULE_DESCRIPTION("NxtWave NXT6000 DVB-T demodulator driver");
 MODULE_AUTHOR("Florian Schirmer");
 MODULE_LICENSE("GPL");

 EXPORT_SYMBOL(nxt6000_attach);
	/*
	NxtWave Communications - NXT6000 demodulator driver

	Copyright (C) 2002-2003 Florian Schirmer <jolt@tuxbox.org>
	Copyright (C) 2003 Paul Andreassen <paul@andreassen.com.au>

	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 <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/slab.h>

	#include "dvb_frontend.h"
	#include "nxt6000_priv.h"
	#include "nxt6000.h"



	struct nxt6000_state {
	struct i2c_adapter* i2c;
	/* configuration settings */
	const struct nxt6000_config* config;
	struct dvb_frontend frontend;
	};

	static int debug;
	#define dprintk if (debug) printk

	static int nxt6000_writereg(struct nxt6000_state* state, u8 reg, u8 data)
	{
	u8 buf[] = { reg, data };
	struct i2c_msg msg = {.addr = state->config->demod_address,.flags = 0,.buf = buf,.len = 2 };
	int ret;

	if ((ret = i2c_transfer(state->i2c, &msg, 1)) != 1)
	dprintk("nxt6000: nxt6000_write error (reg: 0x%02X, data: 0x%02X, ret: %d)\n", reg, data, ret);

	return (ret != 1) ? -EIO : 0;
	}

	static u8 nxt6000_readreg(struct nxt6000_state* state, u8 reg)
	{
	int ret;
	u8 b0[] = { reg };
	u8 b1[] = { 0 };
	struct i2c_msg msgs[] = {
	{.addr = state->config->demod_address,.flags = 0,.buf = b0,.len = 1},
	{.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b1,.len = 1}
	};

	ret = i2c_transfer(state->i2c, msgs, 2);

	if (ret != 2)
	dprintk("nxt6000: nxt6000_read error (reg: 0x%02X, ret: %d)\n", reg, ret);

	return b1[0];
	}

	static void nxt6000_reset(struct nxt6000_state* state)
	{
	u8 val;

	val = nxt6000_readreg(state, OFDM_COR_CTL);

	nxt6000_writereg(state, OFDM_COR_CTL, val & ~COREACT);
	nxt6000_writereg(state, OFDM_COR_CTL, val \| COREACT);
	}

	static int nxt6000_set_bandwidth(struct nxt6000_state *state, u32 bandwidth)
	{
	u16 nominal_rate;
	int result;

	switch (bandwidth) {
	case 6000000:
	nominal_rate = 0x55B7;
	break;

	case 7000000:
	nominal_rate = 0x6400;
	break;

	case 8000000:
	nominal_rate = 0x7249;
	break;

	default:
	return -EINVAL;
	}

	if ((result = nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, nominal_rate & 0xFF)) < 0)
	return result;

	return nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, (nominal_rate >> 8) & 0xFF);
	}

	static int nxt6000_set_guard_interval(struct nxt6000_state* state, fe_guard_interval_t guard_interval)
	{
	switch (guard_interval) {

	case GUARD_INTERVAL_1_32:
	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x00 \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_1_16:
	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x01 \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_AUTO:
	case GUARD_INTERVAL_1_8:
	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x02 \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_1_4:
	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x03 \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	default:
	return -EINVAL;
	}
	}

	static int nxt6000_set_inversion(struct nxt6000_state* state, fe_spectral_inversion_t inversion)
	{
	switch (inversion) {

	case INVERSION_OFF:
	return nxt6000_writereg(state, OFDM_ITB_CTL, 0x00);

	case INVERSION_ON:
	return nxt6000_writereg(state, OFDM_ITB_CTL, ITBINV);

	default:
	return -EINVAL;

	}
	}

	static int nxt6000_set_transmission_mode(struct nxt6000_state* state, fe_transmit_mode_t transmission_mode)
	{
	int result;

	switch (transmission_mode) {

	case TRANSMISSION_MODE_2K:
	if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x00 \| (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
	return result;

	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x00 << 2) \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

	case TRANSMISSION_MODE_8K:
	case TRANSMISSION_MODE_AUTO:
	if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x02 \| (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
	return result;

	return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x01 << 2) \| (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

	default:
	return -EINVAL;

	}
	}

	static void nxt6000_setup(struct dvb_frontend* fe)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_writereg(state, RS_COR_SYNC_PARAM, SYNC_PARAM);
	nxt6000_writereg(state, BER_CTRL, /(1 << 2) \| / (0x01 << 1) \| 0x01);
	nxt6000_writereg(state, VIT_BERTIME_2, 0x00); // BER Timer = 0x000200 * 256 = 131072 bits
	nxt6000_writereg(state, VIT_BERTIME_1, 0x02); //
	nxt6000_writereg(state, VIT_BERTIME_0, 0x00); //
	nxt6000_writereg(state, VIT_COR_INTEN, 0x98); // Enable BER interrupts
	nxt6000_writereg(state, VIT_COR_CTL, 0x82); // Enable BER measurement
	nxt6000_writereg(state, VIT_COR_CTL, VIT_COR_RESYNC \| 0x02 );
	nxt6000_writereg(state, OFDM_COR_CTL, (0x01 << 5) \| (nxt6000_readreg(state, OFDM_COR_CTL) & 0x0F));
	nxt6000_writereg(state, OFDM_COR_MODEGUARD, FORCEMODE8K \| 0x02);
	nxt6000_writereg(state, OFDM_AGC_CTL, AGCLAST \| INITIAL_AGC_BW);
	nxt6000_writereg(state, OFDM_ITB_FREQ_1, 0x06);
	nxt6000_writereg(state, OFDM_ITB_FREQ_2, 0x31);
	nxt6000_writereg(state, OFDM_CAS_CTL, (0x01 << 7) \| (0x02 << 3) \| 0x04);
	nxt6000_writereg(state, CAS_FREQ, 0xBB); /* CHECKME */
	nxt6000_writereg(state, OFDM_SYR_CTL, 1 << 2);
	nxt6000_writereg(state, OFDM_PPM_CTL_1, PPM256);
	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, 0x49);
	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, 0x72);
	nxt6000_writereg(state, ANALOG_CONTROL_0, 1 << 5);
	nxt6000_writereg(state, EN_DMD_RACQ, (1 << 7) \| (3 << 4) \| 2);
	nxt6000_writereg(state, DIAG_CONFIG, TB_SET);

	if (state->config->clock_inversion)
	nxt6000_writereg(state, SUB_DIAG_MODE_SEL, CLKINVERSION);
	else
	nxt6000_writereg(state, SUB_DIAG_MODE_SEL, 0);

	nxt6000_writereg(state, TS_FORMAT, 0);
	}

	static void nxt6000_dump_status(struct nxt6000_state *state)
	{
	u8 val;

	/*
	printk("RS_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, RS_COR_STAT));
	printk("VIT_SYNC_STATUS: 0x%02X\n", nxt6000_readreg(fe, VIT_SYNC_STATUS));
	printk("OFDM_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_COR_STAT));
	printk("OFDM_SYR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_SYR_STAT));
	printk("OFDM_TPS_RCVD_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_1));
	printk("OFDM_TPS_RCVD_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_2));
	printk("OFDM_TPS_RCVD_3: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_3));
	printk("OFDM_TPS_RCVD_4: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_4));
	printk("OFDM_TPS_RESERVED_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_1));
	printk("OFDM_TPS_RESERVED_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_2));
	*/
	printk("NXT6000 status:");

	val = nxt6000_readreg(state, RS_COR_STAT);

	printk(" DATA DESCR LOCK: %d,", val & 0x01);
	printk(" DATA SYNC LOCK: %d,", (val >> 1) & 0x01);

	val = nxt6000_readreg(state, VIT_SYNC_STATUS);

	printk(" VITERBI LOCK: %d,", (val >> 7) & 0x01);

	switch ((val >> 4) & 0x07) {

	case 0x00:
	printk(" VITERBI CODERATE: 1/2,");
	break;

	case 0x01:
	printk(" VITERBI CODERATE: 2/3,");
	break;

	case 0x02:
	printk(" VITERBI CODERATE: 3/4,");
	break;

	case 0x03:
	printk(" VITERBI CODERATE: 5/6,");
	break;

	case 0x04:
	printk(" VITERBI CODERATE: 7/8,");
	break;

	default:
	printk(" VITERBI CODERATE: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_COR_STAT);

	printk(" CHCTrack: %d,", (val >> 7) & 0x01);
	printk(" TPSLock: %d,", (val >> 6) & 0x01);
	printk(" SYRLock: %d,", (val >> 5) & 0x01);
	printk(" AGCLock: %d,", (val >> 4) & 0x01);

	switch (val & 0x0F) {

	case 0x00:
	printk(" CoreState: IDLE,");
	break;

	case 0x02:
	printk(" CoreState: WAIT_AGC,");
	break;

	case 0x03:
	printk(" CoreState: WAIT_SYR,");
	break;

	case 0x04:
	printk(" CoreState: WAIT_PPM,");
	break;

	case 0x01:
	printk(" CoreState: WAIT_TRL,");
	break;

	case 0x05:
	printk(" CoreState: WAIT_TPS,");
	break;

	case 0x06:
	printk(" CoreState: MONITOR_TPS,");
	break;

	default:
	printk(" CoreState: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_SYR_STAT);

	printk(" SYRLock: %d,", (val >> 4) & 0x01);
	printk(" SYRMode: %s,", (val >> 2) & 0x01 ? "8K" : "2K");

	switch ((val >> 4) & 0x03) {

	case 0x00:
	printk(" SYRGuard: 1/32,");
	break;

	case 0x01:
	printk(" SYRGuard: 1/16,");
	break;

	case 0x02:
	printk(" SYRGuard: 1/8,");
	break;

	case 0x03:
	printk(" SYRGuard: 1/4,");
	break;
	}

	val = nxt6000_readreg(state, OFDM_TPS_RCVD_3);

	switch ((val >> 4) & 0x07) {

	case 0x00:
	printk(" TPSLP: 1/2,");
	break;

	case 0x01:
	printk(" TPSLP: 2/3,");
	break;

	case 0x02:
	printk(" TPSLP: 3/4,");
	break;

	case 0x03:
	printk(" TPSLP: 5/6,");
	break;

	case 0x04:
	printk(" TPSLP: 7/8,");
	break;

	default:
	printk(" TPSLP: Reserved,");

	}

	switch (val & 0x07) {

	case 0x00:
	printk(" TPSHP: 1/2,");
	break;

	case 0x01:
	printk(" TPSHP: 2/3,");
	break;

	case 0x02:
	printk(" TPSHP: 3/4,");
	break;

	case 0x03:
	printk(" TPSHP: 5/6,");
	break;

	case 0x04:
	printk(" TPSHP: 7/8,");
	break;

	default:
	printk(" TPSHP: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_TPS_RCVD_4);

	printk(" TPSMode: %s,", val & 0x01 ? "8K" : "2K");

	switch ((val >> 4) & 0x03) {

	case 0x00:
	printk(" TPSGuard: 1/32,");
	break;

	case 0x01:
	printk(" TPSGuard: 1/16,");
	break;

	case 0x02:
	printk(" TPSGuard: 1/8,");
	break;

	case 0x03:
	printk(" TPSGuard: 1/4,");
	break;

	}

	/* Strange magic required to gain access to RF_AGC_STATUS */
	nxt6000_readreg(state, RF_AGC_VAL_1);
	val = nxt6000_readreg(state, RF_AGC_STATUS);
	val = nxt6000_readreg(state, RF_AGC_STATUS);

	printk(" RF AGC LOCK: %d,", (val >> 4) & 0x01);
	printk("\n");
	}

	static int nxt6000_read_status(struct dvb_frontend* fe, fe_status_t* status)
	{
	u8 core_status;
	struct nxt6000_state* state = fe->demodulator_priv;

	*status = 0;

	core_status = nxt6000_readreg(state, OFDM_COR_STAT);

	if (core_status & AGCLOCKED)
	*status \|= FE_HAS_SIGNAL;

	if (nxt6000_readreg(state, OFDM_SYR_STAT) & GI14_SYR_LOCK)
	*status \|= FE_HAS_CARRIER;

	if (nxt6000_readreg(state, VIT_SYNC_STATUS) & VITINSYNC)
	*status \|= FE_HAS_VITERBI;

	if (nxt6000_readreg(state, RS_COR_STAT) & RSCORESTATUS)
	*status \|= FE_HAS_SYNC;

	if ((core_status & TPSLOCKED) && (*status == (FE_HAS_SIGNAL \| FE_HAS_CARRIER \| FE_HAS_VITERBI \| FE_HAS_SYNC)))
	*status \|= FE_HAS_LOCK;

	if (debug)
	nxt6000_dump_status(state);

	return 0;
	}

	static int nxt6000_init(struct dvb_frontend* fe)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_reset(state);
	nxt6000_setup(fe);

	return 0;
	}

	static int nxt6000_set_frontend(struct dvb_frontend *fe)
	{
	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
	struct nxt6000_state* state = fe->demodulator_priv;
	int result;

	if (fe->ops.tuner_ops.set_params) {
	fe->ops.tuner_ops.set_params(fe);
	if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
	}

	result = nxt6000_set_bandwidth(state, p->bandwidth_hz);
	if (result < 0)
	return result;

	result = nxt6000_set_guard_interval(state, p->guard_interval);
	if (result < 0)
	return result;

	result = nxt6000_set_transmission_mode(state, p->transmission_mode);
	if (result < 0)
	return result;

	result = nxt6000_set_inversion(state, p->inversion);
	if (result < 0)
	return result;

	msleep(500);
	return 0;
	}

	static void nxt6000_release(struct dvb_frontend* fe)
	{
	struct nxt6000_state* state = fe->demodulator_priv;
	kfree(state);
	}

	static int nxt6000_read_snr(struct dvb_frontend* fe, u16* snr)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	*snr = nxt6000_readreg( state, OFDM_CHC_SNR) / 8;

	return 0;
	}

	static int nxt6000_read_ber(struct dvb_frontend* fe, u32* ber)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18 );

	*ber = (nxt6000_readreg( state, VIT_BER_1 ) << 8 ) \|
	nxt6000_readreg( state, VIT_BER_0 );

	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18); // Clear BER Done interrupts

	return 0;
	}

	static int nxt6000_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	*signal_strength = (short) (511 -
	(nxt6000_readreg(state, AGC_GAIN_1) +
	((nxt6000_readreg(state, AGC_GAIN_2) & 0x03) << 8)));

	return 0;
	}

	static int nxt6000_fe_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings *tune)
	{
	tune->min_delay_ms = 500;
	return 0;
	}

	static int nxt6000_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
	{
	struct nxt6000_state* state = fe->demodulator_priv;

	if (enable) {
	return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x01);
	} else {
	return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x00);
	}
	}

	static struct dvb_frontend_ops nxt6000_ops;

	struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config,
	struct i2c_adapter* i2c)
	{
	struct nxt6000_state* state = NULL;

	/* allocate memory for the internal state */
	state = kzalloc(sizeof(struct nxt6000_state), GFP_KERNEL);
	if (state == NULL) goto error;

	/* setup the state */
	state->config = config;
	state->i2c = i2c;

	/* check if the demod is there */
	if (nxt6000_readreg(state, OFDM_MSC_REV) != NXT6000ASICDEVICE) goto error;

	/* create dvb_frontend */
	memcpy(&state->frontend.ops, &nxt6000_ops, sizeof(struct dvb_frontend_ops));
	state->frontend.demodulator_priv = state;
	return &state->frontend;

	error:
	kfree(state);
	return NULL;
	}

	static struct dvb_frontend_ops nxt6000_ops = {
	.delsys = { SYS_DVBT },
	.info = {
	.name = "NxtWave NXT6000 DVB-T",
	.frequency_min = 0,
	.frequency_max = 863250000,
	.frequency_stepsize = 62500,
	/.frequency_tolerance = //* FIXME: 12% of SR */
	.symbol_rate_min = 0, /* FIXME */
	.symbol_rate_max = 9360000, /* FIXME */
	.symbol_rate_tolerance = 4000,
	.caps = FE_CAN_FEC_1_2 \| FE_CAN_FEC_2_3 \| FE_CAN_FEC_3_4 \|
	FE_CAN_FEC_4_5 \| FE_CAN_FEC_5_6 \| FE_CAN_FEC_6_7 \|
	FE_CAN_FEC_7_8 \| FE_CAN_FEC_8_9 \| FE_CAN_FEC_AUTO \|
	FE_CAN_QAM_16 \| FE_CAN_QAM_64 \| FE_CAN_QAM_AUTO \|
	FE_CAN_TRANSMISSION_MODE_AUTO \| FE_CAN_GUARD_INTERVAL_AUTO \|
	FE_CAN_HIERARCHY_AUTO,
	},

	.release = nxt6000_release,

	.init = nxt6000_init,
	.i2c_gate_ctrl = nxt6000_i2c_gate_ctrl,

	.get_tune_settings = nxt6000_fe_get_tune_settings,

	.set_frontend = nxt6000_set_frontend,

	.read_status = nxt6000_read_status,
	.read_ber = nxt6000_read_ber,
	.read_signal_strength = nxt6000_read_signal_strength,
	.read_snr = nxt6000_read_snr,
	};

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

	MODULE_DESCRIPTION("NxtWave NXT6000 DVB-T demodulator driver");
	MODULE_AUTHOR("Florian Schirmer");
	MODULE_LICENSE("GPL");

	EXPORT_SYMBOL(nxt6000_attach);