/*
 * TerraTec Cinergy T2/qanu USB2 DVB-T adapter.
 *
 * Copyright (C) 2007 Tomi Orava (tomimo@ncircle.nullnet.fi)
 *
 * Based on the dvb-usb-framework code and the
 * original Terratec Cinergy T2 driver by:
 *
 * Copyright (C) 2004 Daniel Mack <daniel@qanu.de> and
 *                  Holger Waechtler <holger@qanu.de>
 *
 *  Protocol Spec published on http://qanu.de/specs/terratec_cinergyT2.pdf
 *
 * 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 "cinergyT2.h"


/**
 *  convert linux-dvb frontend parameter set into TPS.
 *  See ETSI ETS-300744, section 4.6.2, table 9 for details.
 *
 *  This function is probably reusable and may better get placed in a support
 *  library.
 *
 *  We replace errornous fields by default TPS fields (the ones with value 0).
 */

static uint16_t compute_tps(struct dtv_frontend_properties *op)
{
        uint16_t tps = 0;

        switch (op->code_rate_HP) {
        case FEC_2_3:
                tps |= (1 << 7);
                break;
        case FEC_3_4:
                tps |= (2 << 7);
                break;
        case FEC_5_6:
                tps |= (3 << 7);
                break;
        case FEC_7_8:
                tps |= (4 << 7);
                break;
        case FEC_1_2:
        case FEC_AUTO:
        default:
                /* tps |= (0 << 7) */;
        }

        switch (op->code_rate_LP) {
        case FEC_2_3:
                tps |= (1 << 4);
                break;
        case FEC_3_4:
                tps |= (2 << 4);
                break;
        case FEC_5_6:
                tps |= (3 << 4);
                break;
        case FEC_7_8:
                tps |= (4 << 4);
                break;
        case FEC_1_2:
        case FEC_AUTO:
        default:
                /* tps |= (0 << 4) */;
        }

        switch (op->modulation) {
        case QAM_16:
                tps |= (1 << 13);
                break;
        case QAM_64:
                tps |= (2 << 13);
                break;
        case QPSK:
        default:
                /* tps |= (0 << 13) */;
        }

        switch (op->transmission_mode) {
        case TRANSMISSION_MODE_8K:
                tps |= (1 << 0);
                break;
        case TRANSMISSION_MODE_2K:
        default:
                /* tps |= (0 << 0) */;
        }

        switch (op->guard_interval) {
        case GUARD_INTERVAL_1_16:
                tps |= (1 << 2);
                break;
        case GUARD_INTERVAL_1_8:
                tps |= (2 << 2);
                break;
        case GUARD_INTERVAL_1_4:
                tps |= (3 << 2);
                break;
        case GUARD_INTERVAL_1_32:
        default:
                /* tps |= (0 << 2) */;
        }

        switch (op->hierarchy) {
        case HIERARCHY_1:
                tps |= (1 << 10);
                break;
        case HIERARCHY_2:
                tps |= (2 << 10);
                break;
        case HIERARCHY_4:
                tps |= (3 << 10);
                break;
        case HIERARCHY_NONE:
        default:
                /* tps |= (0 << 10) */;
        }

        return tps;
}

struct cinergyt2_fe_state {
        struct dvb_frontend fe;
        struct dvb_usb_device *d;
};

static int cinergyt2_fe_read_status(struct dvb_frontend *fe,
                                        fe_status_t *status)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_get_status_msg result;
        u8 cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
        int ret;

        ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (u8 *)&result,
                        sizeof(result), 0);
        if (ret < 0)
                return ret;

        *status = 0;

        if (0xffff - le16_to_cpu(result.gain) > 30)
                *status |= FE_HAS_SIGNAL;
        if (result.lock_bits & (1 << 6))
                *status |= FE_HAS_LOCK;
        if (result.lock_bits & (1 << 5))
                *status |= FE_HAS_SYNC;
        if (result.lock_bits & (1 << 4))
                *status |= FE_HAS_CARRIER;
        if (result.lock_bits & (1 << 1))
                *status |= FE_HAS_VITERBI;

        if ((*status & (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)) !=
                        (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC))
                *status &= ~FE_HAS_LOCK;

        return 0;
}

static int cinergyt2_fe_read_ber(struct dvb_frontend *fe, u32 *ber)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_get_status_msg status;
        char cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
        int ret;

        ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (char *)&status,
                                sizeof(status), 0);
        if (ret < 0)
                return ret;

        *ber = le32_to_cpu(status.viterbi_error_rate);
        return 0;
}

static int cinergyt2_fe_read_unc_blocks(struct dvb_frontend *fe, u32 *unc)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_get_status_msg status;
        u8 cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
        int ret;

        ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (u8 *)&status,
                                sizeof(status), 0);
        if (ret < 0) {
                err("cinergyt2_fe_read_unc_blocks() Failed! (Error=%d)\n",
                        ret);
                return ret;
        }
        *unc = le32_to_cpu(status.uncorrected_block_count);
        return 0;
}

static int cinergyt2_fe_read_signal_strength(struct dvb_frontend *fe,
                                                u16 *strength)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_get_status_msg status;
        char cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
        int ret;

        ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (char *)&status,
                                sizeof(status), 0);
        if (ret < 0) {
                err("cinergyt2_fe_read_signal_strength() Failed!"
                        " (Error=%d)\n", ret);
                return ret;
        }
        *strength = (0xffff - le16_to_cpu(status.gain));
        return 0;
}

static int cinergyt2_fe_read_snr(struct dvb_frontend *fe, u16 *snr)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_get_status_msg status;
        char cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
        int ret;

        ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (char *)&status,
                                sizeof(status), 0);
        if (ret < 0) {
                err("cinergyt2_fe_read_snr() Failed! (Error=%d)\n", ret);
                return ret;
        }
        *snr = (status.snr << 8) | status.snr;
        return 0;
}

static int cinergyt2_fe_init(struct dvb_frontend *fe)
{
        return 0;
}

static int cinergyt2_fe_sleep(struct dvb_frontend *fe)
{
        deb_info("cinergyt2_fe_sleep() Called\n");
        return 0;
}

static int cinergyt2_fe_get_tune_settings(struct dvb_frontend *fe,
                                struct dvb_frontend_tune_settings *tune)
{
        tune->min_delay_ms = 800;
        return 0;
}

static int cinergyt2_fe_set_frontend(struct dvb_frontend *fe)
{
        struct dtv_frontend_properties *fep = &fe->dtv_property_cache;
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        struct dvbt_set_parameters_msg param;
        char result[2];
        int err;

        param.cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS;
        param.tps = cpu_to_le16(compute_tps(fep));
        param.freq = cpu_to_le32(fep->frequency / 1000);
        param.flags = 0;

        switch (fep->bandwidth_hz) {
        default:
        case 8000000:
                param.bandwidth = 8;
                break;
        case 7000000:
                param.bandwidth = 7;
                break;
        case 6000000:
                param.bandwidth = 6;
                break;
        }

        err = dvb_usb_generic_rw(state->d,
                        (char *)&param, sizeof(param),
                        result, sizeof(result), 0);
        if (err < 0)
                err("cinergyt2_fe_set_frontend() Failed! err=%d\n", err);

        return (err < 0) ? err : 0;
}

static void cinergyt2_fe_release(struct dvb_frontend *fe)
{
        struct cinergyt2_fe_state *state = fe->demodulator_priv;
        kfree(state);
}

static struct dvb_frontend_ops cinergyt2_fe_ops;

struct dvb_frontend *cinergyt2_fe_attach(struct dvb_usb_device *d)
{
        struct cinergyt2_fe_state *s = kzalloc(sizeof(
                                        struct cinergyt2_fe_state), GFP_KERNEL);
        if (s == NULL)
                return NULL;

        s->d = d;
        memcpy(&s->fe.ops, &cinergyt2_fe_ops, sizeof(struct dvb_frontend_ops));
        s->fe.demodulator_priv = s;
        return &s->fe;
}


static struct dvb_frontend_ops cinergyt2_fe_ops = {
        .delsys = { SYS_DVBT },
        .info = {
                .name                   = DRIVER_NAME,
                .frequency_min          = 174000000,
                .frequency_max          = 862000000,
                .frequency_stepsize     = 166667,
                .caps = FE_CAN_INVERSION_AUTO | 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_TRANSMISSION_MODE_AUTO
                        | FE_CAN_GUARD_INTERVAL_AUTO
                        | FE_CAN_HIERARCHY_AUTO
                        | FE_CAN_RECOVER
                        | FE_CAN_MUTE_TS
        },

        .release                = cinergyt2_fe_release,

        .init                   = cinergyt2_fe_init,
        .sleep                  = cinergyt2_fe_sleep,

        .set_frontend           = cinergyt2_fe_set_frontend,
        .get_tune_settings      = cinergyt2_fe_get_tune_settings,

        .read_status            = cinergyt2_fe_read_status,
        .read_ber               = cinergyt2_fe_read_ber,
        .read_signal_strength   = cinergyt2_fe_read_signal_strength,
        .read_snr               = cinergyt2_fe_read_snr,
        .read_ucblocks          = cinergyt2_fe_read_unc_blocks,
};