nxt6000.c

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/*
    NxtWave Communications - NXT6000 demodulator driver

    Copyright (C) 2002-2003 Florian Schirmer <[email protected]>
    Copyright (C) 2003 Paul Andreassen <[email protected]>

    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);