mxl111sf-demod.c

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/*
 *  mxl111sf-demod.c - driver for the MaxLinear MXL111SF DVB-T demodulator
 *
 *  Copyright (C) 2010 Michael Krufky <[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 "mxl111sf-demod.h"
#include "mxl111sf-reg.h"

/* debug */
static int mxl111sf_demod_debug;
module_param_named(debug, mxl111sf_demod_debug, int, 0644);
MODULE_PARM_DESC(debug, "set debugging level (1=info (or-able)).");

#define mxl_dbg(fmt, arg...) \
    if (mxl111sf_demod_debug) \
        mxl_printk(KERN_DEBUG, fmt, ##arg)

/* ------------------------------------------------------------------------ */

struct mxl111sf_demod_state {
    struct mxl111sf_state *mxl_state;

    struct mxl111sf_demod_config *cfg;

    struct dvb_frontend fe;
};

/* ------------------------------------------------------------------------ */

static int mxl111sf_demod_read_reg(struct mxl111sf_demod_state *state,
                   u8 addr, u8 *data)
{
    return (state->cfg->read_reg) ?
        state->cfg->read_reg(state->mxl_state, addr, data) :
        -EINVAL;
}

static int mxl111sf_demod_write_reg(struct mxl111sf_demod_state *state,
                    u8 addr, u8 data)
{
    return (state->cfg->write_reg) ?
        state->cfg->write_reg(state->mxl_state, addr, data) :
        -EINVAL;
}

static
int mxl111sf_demod_program_regs(struct mxl111sf_demod_state *state,
                struct mxl111sf_reg_ctrl_info *ctrl_reg_info)
{
    return (state->cfg->program_regs) ?
        state->cfg->program_regs(state->mxl_state, ctrl_reg_info) :
        -EINVAL;
}

/* ------------------------------------------------------------------------ */
/* TPS */

static
int mxl1x1sf_demod_get_tps_code_rate(struct mxl111sf_demod_state *state,
                     fe_code_rate_t *code_rate)
{
    u8 val;
    int ret = mxl111sf_demod_read_reg(state, V6_CODE_RATE_TPS_REG, &val);
    /* bit<2:0> - 000:1/2, 001:2/3, 010:3/4, 011:5/6, 100:7/8 */
    if (mxl_fail(ret))
        goto fail;

    switch (val & V6_CODE_RATE_TPS_MASK) {
    case 0:
        *code_rate = FEC_1_2;
        break;
    case 1:
        *code_rate = FEC_2_3;
        break;
    case 2:
        *code_rate = FEC_3_4;
        break;
    case 3:
        *code_rate = FEC_5_6;
        break;
    case 4:
        *code_rate = FEC_7_8;
        break;
    }
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_tps_modulation(struct mxl111sf_demod_state *state,
                     fe_modulation_t *modulation)
{
    u8 val;
    int ret = mxl111sf_demod_read_reg(state, V6_MODORDER_TPS_REG, &val);
    /* Constellation, 00 : QPSK, 01 : 16QAM, 10:64QAM */
    if (mxl_fail(ret))
        goto fail;

    switch ((val & V6_PARAM_CONSTELLATION_MASK) >> 4) {
    case 0:
        *modulation = QPSK;
        break;
    case 1:
        *modulation = QAM_16;
        break;
    case 2:
        *modulation = QAM_64;
        break;
    }
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_tps_guard_fft_mode(struct mxl111sf_demod_state *state,
                      fe_transmit_mode_t *fft_mode)
{
    u8 val;
    int ret = mxl111sf_demod_read_reg(state, V6_MODE_TPS_REG, &val);
    /* FFT Mode, 00:2K, 01:8K, 10:4K */
    if (mxl_fail(ret))
        goto fail;

    switch ((val & V6_PARAM_FFT_MODE_MASK) >> 2) {
    case 0:
        *fft_mode = TRANSMISSION_MODE_2K;
        break;
    case 1:
        *fft_mode = TRANSMISSION_MODE_8K;
        break;
    case 2:
        *fft_mode = TRANSMISSION_MODE_4K;
        break;
    }
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_tps_guard_interval(struct mxl111sf_demod_state *state,
                      fe_guard_interval_t *guard)
{
    u8 val;
    int ret = mxl111sf_demod_read_reg(state, V6_CP_TPS_REG, &val);
    /* 00:1/32, 01:1/16, 10:1/8, 11:1/4 */
    if (mxl_fail(ret))
        goto fail;

    switch ((val & V6_PARAM_GI_MASK) >> 4) {
    case 0:
        *guard = GUARD_INTERVAL_1_32;
        break;
    case 1:
        *guard = GUARD_INTERVAL_1_16;
        break;
    case 2:
        *guard = GUARD_INTERVAL_1_8;
        break;
    case 3:
        *guard = GUARD_INTERVAL_1_4;
        break;
    }
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_tps_hierarchy(struct mxl111sf_demod_state *state,
                     fe_hierarchy_t *hierarchy)
{
    u8 val;
    int ret = mxl111sf_demod_read_reg(state, V6_TPS_HIERACHY_REG, &val);
    /* bit<6:4> - 000:Non hierarchy, 001:1, 010:2, 011:4 */
    if (mxl_fail(ret))
        goto fail;

    switch ((val & V6_TPS_HIERARCHY_INFO_MASK) >> 6) {
    case 0:
        *hierarchy = HIERARCHY_NONE;
        break;
    case 1:
        *hierarchy = HIERARCHY_1;
        break;
    case 2:
        *hierarchy = HIERARCHY_2;
        break;
    case 3:
        *hierarchy = HIERARCHY_4;
        break;
    }
fail:
    return ret;
}

/* ------------------------------------------------------------------------ */
/* LOCKS */

static
int mxl1x1sf_demod_get_sync_lock_status(struct mxl111sf_demod_state *state,
                    int *sync_lock)
{
    u8 val = 0;
    int ret = mxl111sf_demod_read_reg(state, V6_SYNC_LOCK_REG, &val);
    if (mxl_fail(ret))
        goto fail;
    *sync_lock = (val & SYNC_LOCK_MASK) >> 4;
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_rs_lock_status(struct mxl111sf_demod_state *state,
                      int *rs_lock)
{
    u8 val = 0;
    int ret = mxl111sf_demod_read_reg(state, V6_RS_LOCK_DET_REG, &val);
    if (mxl_fail(ret))
        goto fail;
    *rs_lock = (val & RS_LOCK_DET_MASK) >> 3;
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_tps_lock_status(struct mxl111sf_demod_state *state,
                       int *tps_lock)
{
    u8 val = 0;
    int ret = mxl111sf_demod_read_reg(state, V6_TPS_LOCK_REG, &val);
    if (mxl_fail(ret))
        goto fail;
    *tps_lock = (val & V6_PARAM_TPS_LOCK_MASK) >> 6;
fail:
    return ret;
}

static
int mxl1x1sf_demod_get_fec_lock_status(struct mxl111sf_demod_state *state,
                       int *fec_lock)
{
    u8 val = 0;
    int ret = mxl111sf_demod_read_reg(state, V6_IRQ_STATUS_REG, &val);
    if (mxl_fail(ret))
        goto fail;
    *fec_lock = (val & IRQ_MASK_FEC_LOCK) >> 4;
fail:
    return ret;
}

#if 0
static
int mxl1x1sf_demod_get_cp_lock_status(struct mxl111sf_demod_state *state,
                      int *cp_lock)
{
    u8 val = 0;
    int ret = mxl111sf_demod_read_reg(state, V6_CP_LOCK_DET_REG, &val);
    if (mxl_fail(ret))
        goto fail;
    *cp_lock = (val & V6_CP_LOCK_DET_MASK) >> 2;
fail:
    return ret;
}
#endif

static int mxl1x1sf_demod_reset_irq_status(struct mxl111sf_demod_state *state)
{
    return mxl111sf_demod_write_reg(state, 0x0e, 0xff);
}

/* ------------------------------------------------------------------------ */

static int mxl111sf_demod_set_frontend(struct dvb_frontend *fe)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    int ret = 0;

    struct mxl111sf_reg_ctrl_info phy_pll_patch[] = {
        {0x00, 0xff, 0x01}, /* change page to 1 */
        {0x40, 0xff, 0x05},
        {0x40, 0xff, 0x01},
        {0x41, 0xff, 0xca},
        {0x41, 0xff, 0xc0},
        {0x00, 0xff, 0x00}, /* change page to 0 */
        {0,    0,    0}
    };

    mxl_dbg("()");

    if (fe->ops.tuner_ops.set_params) {
        ret = fe->ops.tuner_ops.set_params(fe);
        if (mxl_fail(ret))
            goto fail;
        msleep(50);
    }
    ret = mxl111sf_demod_program_regs(state, phy_pll_patch);
    mxl_fail(ret);
    msleep(50);
    ret = mxl1x1sf_demod_reset_irq_status(state);
    mxl_fail(ret);
    msleep(100);
fail:
    return ret;
}

/* ------------------------------------------------------------------------ */

#if 0
/* resets TS Packet error count */
/* After setting 7th bit of V5_PER_COUNT_RESET_REG, it should be reset to 0. */
static
int mxl1x1sf_demod_reset_packet_error_count(struct mxl111sf_demod_state *state)
{
    struct mxl111sf_reg_ctrl_info reset_per_count[] = {
        {0x20, 0x01, 0x01},
        {0x20, 0x01, 0x00},
        {0,    0,    0}
    };
    return mxl111sf_demod_program_regs(state, reset_per_count);
}
#endif

/* returns TS Packet error count */
/* PER Count = FEC_PER_COUNT * (2 ** (FEC_PER_SCALE * 4)) */
static int mxl111sf_demod_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    u32 fec_per_count, fec_per_scale;
    u8 val;
    int ret;

    *ucblocks = 0;

    /* FEC_PER_COUNT Register */
    ret = mxl111sf_demod_read_reg(state, V6_FEC_PER_COUNT_REG, &val);
    if (mxl_fail(ret))
        goto fail;

    fec_per_count = val;

    /* FEC_PER_SCALE Register */
    ret = mxl111sf_demod_read_reg(state, V6_FEC_PER_SCALE_REG, &val);
    if (mxl_fail(ret))
        goto fail;

    val &= V6_FEC_PER_SCALE_MASK;
    val *= 4;

    fec_per_scale = 1 << val;

    fec_per_count *= fec_per_scale;

    *ucblocks = fec_per_count;
fail:
    return ret;
}

#ifdef MXL111SF_DEMOD_ENABLE_CALCULATIONS
/* FIXME: leaving this enabled breaks the build on some architectures,
 * and we shouldn't have any floating point math in the kernel, anyway.
 *
 * These macros need to be re-written, but it's harmless to simply
 * return zero for now. */
#define CALCULATE_BER(avg_errors, count) \
    ((u32)(avg_errors * 4)/(count*64*188*8))
#define CALCULATE_SNR(data) \
    ((u32)((10 * (u32)data / 64) - 2.5))
#else
#define CALCULATE_BER(avg_errors, count) 0
#define CALCULATE_SNR(data) 0
#endif

static int mxl111sf_demod_read_ber(struct dvb_frontend *fe, u32 *ber)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    u8 val1, val2, val3;
    int ret;

    *ber = 0;

    ret = mxl111sf_demod_read_reg(state, V6_RS_AVG_ERRORS_LSB_REG, &val1);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl111sf_demod_read_reg(state, V6_RS_AVG_ERRORS_MSB_REG, &val2);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl111sf_demod_read_reg(state, V6_N_ACCUMULATE_REG, &val3);
    if (mxl_fail(ret))
        goto fail;

    *ber = CALCULATE_BER((val1 | (val2 << 8)), val3);
fail:
    return ret;
}

static int mxl111sf_demod_calc_snr(struct mxl111sf_demod_state *state,
                   u16 *snr)
{
    u8 val1, val2;
    int ret;

    *snr = 0;

    ret = mxl111sf_demod_read_reg(state, V6_SNR_RB_LSB_REG, &val1);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl111sf_demod_read_reg(state, V6_SNR_RB_MSB_REG, &val2);
    if (mxl_fail(ret))
        goto fail;

    *snr = CALCULATE_SNR(val1 | ((val2 & 0x03) << 8));
fail:
    return ret;
}

static int mxl111sf_demod_read_snr(struct dvb_frontend *fe, u16 *snr)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;

    int ret = mxl111sf_demod_calc_snr(state, snr);
    if (mxl_fail(ret))
        goto fail;

    *snr /= 10; /* 0.1 dB */
fail:
    return ret;
}

static int mxl111sf_demod_read_status(struct dvb_frontend *fe,
                      fe_status_t *status)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    int ret, locked, cr_lock, sync_lock, fec_lock;

    *status = 0;

    ret = mxl1x1sf_demod_get_rs_lock_status(state, &locked);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl1x1sf_demod_get_tps_lock_status(state, &cr_lock);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl1x1sf_demod_get_sync_lock_status(state, &sync_lock);
    if (mxl_fail(ret))
        goto fail;
    ret = mxl1x1sf_demod_get_fec_lock_status(state, &fec_lock);
    if (mxl_fail(ret))
        goto fail;

    if (locked)
        *status |= FE_HAS_SIGNAL;
    if (cr_lock)
        *status |= FE_HAS_CARRIER;
    if (sync_lock)
        *status |= FE_HAS_SYNC;
    if (fec_lock) /* false positives? */
        *status |= FE_HAS_VITERBI;

    if ((locked) && (cr_lock) && (sync_lock))
        *status |= FE_HAS_LOCK;
fail:
    return ret;
}

static int mxl111sf_demod_read_signal_strength(struct dvb_frontend *fe,
                           u16 *signal_strength)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    fe_modulation_t modulation;
    u16 snr;

    mxl111sf_demod_calc_snr(state, &snr);
    mxl1x1sf_demod_get_tps_modulation(state, &modulation);

    switch (modulation) {
    case QPSK:
        *signal_strength = (snr >= 1300) ?
            min(65535, snr * 44) : snr * 38;
        break;
    case QAM_16:
        *signal_strength = (snr >= 1500) ?
            min(65535, snr * 38) : snr * 33;
        break;
    case QAM_64:
        *signal_strength = (snr >= 2000) ?
            min(65535, snr * 29) : snr * 25;
        break;
    default:
        *signal_strength = 0;
        return -EINVAL;
    }

    return 0;
}

static int mxl111sf_demod_get_frontend(struct dvb_frontend *fe)
{
    struct dtv_frontend_properties *p = &fe->dtv_property_cache;
    struct mxl111sf_demod_state *state = fe->demodulator_priv;

    mxl_dbg("()");
#if 0
    p->inversion = /* FIXME */ ? INVERSION_ON : INVERSION_OFF;
#endif
    if (fe->ops.tuner_ops.get_bandwidth)
        fe->ops.tuner_ops.get_bandwidth(fe, &p->bandwidth_hz);
    if (fe->ops.tuner_ops.get_frequency)
        fe->ops.tuner_ops.get_frequency(fe, &p->frequency);
    mxl1x1sf_demod_get_tps_code_rate(state, &p->code_rate_HP);
    mxl1x1sf_demod_get_tps_code_rate(state, &p->code_rate_LP);
    mxl1x1sf_demod_get_tps_modulation(state, &p->modulation);
    mxl1x1sf_demod_get_tps_guard_fft_mode(state,
                          &p->transmission_mode);
    mxl1x1sf_demod_get_tps_guard_interval(state,
                          &p->guard_interval);
    mxl1x1sf_demod_get_tps_hierarchy(state,
                     &p->hierarchy);

    return 0;
}

static
int mxl111sf_demod_get_tune_settings(struct dvb_frontend *fe,
                     struct dvb_frontend_tune_settings *tune)
{
    tune->min_delay_ms = 1000;
    return 0;
}

static void mxl111sf_demod_release(struct dvb_frontend *fe)
{
    struct mxl111sf_demod_state *state = fe->demodulator_priv;
    mxl_dbg("()");
    kfree(state);
    fe->demodulator_priv = NULL;
}

static struct dvb_frontend_ops mxl111sf_demod_ops = {
    .delsys = { SYS_DVBT },
    .info = {
        .name               = "MaxLinear MxL111SF DVB-T demodulator",
        .frequency_min      = 177000000,
        .frequency_max      = 858000000,
        .frequency_stepsize = 166666,
        .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
            FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
            FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
            FE_CAN_QAM_AUTO |
            FE_CAN_HIERARCHY_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
            FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_RECOVER
    },
    .release              = mxl111sf_demod_release,
#if 0
    .init                 = mxl111sf_init,
    .i2c_gate_ctrl        = mxl111sf_i2c_gate_ctrl,
#endif
    .set_frontend         = mxl111sf_demod_set_frontend,
    .get_frontend         = mxl111sf_demod_get_frontend,
    .get_tune_settings    = mxl111sf_demod_get_tune_settings,
    .read_status          = mxl111sf_demod_read_status,
    .read_signal_strength = mxl111sf_demod_read_signal_strength,
    .read_ber             = mxl111sf_demod_read_ber,
    .read_snr             = mxl111sf_demod_read_snr,
    .read_ucblocks        = mxl111sf_demod_read_ucblocks,
};

struct dvb_frontend *mxl111sf_demod_attach(struct mxl111sf_state *mxl_state,
                       struct mxl111sf_demod_config *cfg)
{
    struct mxl111sf_demod_state *state = NULL;

    mxl_dbg("()");

    state = kzalloc(sizeof(struct mxl111sf_demod_state), GFP_KERNEL);
    if (state == NULL)
        return NULL;

    state->mxl_state = mxl_state;
    state->cfg = cfg;

    memcpy(&state->fe.ops, &mxl111sf_demod_ops,
           sizeof(struct dvb_frontend_ops));

    state->fe.demodulator_priv = state;
    return &state->fe;
}
EXPORT_SYMBOL_GPL(mxl111sf_demod_attach);

MODULE_DESCRIPTION("MaxLinear MxL111SF DVB-T demodulator driver");
MODULE_AUTHOR("Michael Krufky <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.1");

/*
 * Local variables:
 * c-basic-offset: 8
 * End:
 */