// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  mxl111sf-demod.c - driver for the MaxLinear MXL111SF DVB-T demodulator
 *
 *  Copyright (C) 2010-2014 Michael Krufky <mkrufky@linuxtv.org>
 */

#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;

        const 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,
                                     enum fe_code_rate *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,
                                      enum fe_modulation *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,
                                          enum fe_transmit_mode *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,
                                          enum fe_guard_interval *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,
                                     enum fe_hierarchy *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,
                                      enum fe_status *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;
        enum fe_modulation modulation;
        int ret;
        u16 snr;

        ret = mxl111sf_demod_calc_snr(state, &snr);
        if (ret < 0)
                return ret;
        ret = mxl1x1sf_demod_get_tps_modulation(state, &modulation);
        if (ret < 0)
                return ret;

        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)
{
        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 const struct dvb_frontend_ops mxl111sf_demod_ops = {
        .delsys = { SYS_DVBT },
        .info = {
                .name               = "MaxLinear MxL111SF DVB-T demodulator",
                .frequency_min_hz      = 177 * MHz,
                .frequency_max_hz      = 858 * MHz,
                .frequency_stepsize_hz = 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,
                                   const struct mxl111sf_demod_config *cfg)
{
        struct mxl111sf_demod_state *state = NULL;

        mxl_dbg("()");

        state = kzalloc_obj(struct mxl111sf_demod_state);
        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 <mkrufky@linuxtv.org>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.1");