/*
 * Fitipower FC0013 tuner driver
 *
 * Copyright (C) 2012 Hans-Frieder Vogt <hfvogt@gmx.net>
 * partially based on driver code from Fitipower
 * Copyright (C) 2010 Fitipower Integrated Technology Inc
 *
 *    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 "fc0013.h"
#include "fc0013-priv.h"

static int fc0013_writereg(struct fc0013_priv *priv, u8 reg, u8 val)
{
        u8 buf[2] = {reg, val};
        struct i2c_msg msg = {
                .addr = priv->addr, .flags = 0, .buf = buf, .len = 2
        };

        if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
                err("I2C write reg failed, reg: %02x, val: %02x", reg, val);
                return -EREMOTEIO;
        }
        return 0;
}

static int fc0013_readreg(struct fc0013_priv *priv, u8 reg, u8 *val)
{
        struct i2c_msg msg[2] = {
                { .addr = priv->addr, .flags = 0, .buf = &reg, .len = 1 },
                { .addr = priv->addr, .flags = I2C_M_RD, .buf = val, .len = 1 },
        };

        if (i2c_transfer(priv->i2c, msg, 2) != 2) {
                err("I2C read reg failed, reg: %02x", reg);
                return -EREMOTEIO;
        }
        return 0;
}

static int fc0013_release(struct dvb_frontend *fe)
{
        kfree(fe->tuner_priv);
        fe->tuner_priv = NULL;
        return 0;
}

static int fc0013_init(struct dvb_frontend *fe)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        int i, ret = 0;
        unsigned char reg[] = {
                0x00,   /* reg. 0x00: dummy */
                0x09,   /* reg. 0x01 */
                0x16,   /* reg. 0x02 */
                0x00,   /* reg. 0x03 */
                0x00,   /* reg. 0x04 */
                0x17,   /* reg. 0x05 */
                0x02,   /* reg. 0x06 */
                0x0a,   /* reg. 0x07: CHECK */
                0xff,   /* reg. 0x08: AGC Clock divide by 256, AGC gain 1/256,
                           Loop Bw 1/8 */
                0x6f,   /* reg. 0x09: enable LoopThrough */
                0xb8,   /* reg. 0x0a: Disable LO Test Buffer */
                0x82,   /* reg. 0x0b: CHECK */
                0xfc,   /* reg. 0x0c: depending on AGC Up-Down mode, may need 0xf8 */
                0x01,   /* reg. 0x0d: AGC Not Forcing & LNA Forcing, may need 0x02 */
                0x00,   /* reg. 0x0e */
                0x00,   /* reg. 0x0f */
                0x00,   /* reg. 0x10 */
                0x00,   /* reg. 0x11 */
                0x00,   /* reg. 0x12 */
                0x00,   /* reg. 0x13 */
                0x50,   /* reg. 0x14: DVB-t High Gain, UHF.
                           Middle Gain: 0x48, Low Gain: 0x40 */
                0x01,   /* reg. 0x15 */
        };

        switch (priv->xtal_freq) {
        case FC_XTAL_27_MHZ:
        case FC_XTAL_28_8_MHZ:
                reg[0x07] |= 0x20;
                break;
        case FC_XTAL_36_MHZ:
        default:
                break;
        }

        if (priv->dual_master)
                reg[0x0c] |= 0x02;

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

        for (i = 1; i < sizeof(reg); i++) {
                ret = fc0013_writereg(priv, i, reg[i]);
                if (ret)
                        break;
        }

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

        if (ret)
                err("fc0013_writereg failed: %d", ret);

        return ret;
}

static int fc0013_sleep(struct dvb_frontend *fe)
{
        /* nothing to do here */
        return 0;
}

int fc0013_rc_cal_add(struct dvb_frontend *fe, int rc_val)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        int ret;
        u8 rc_cal;
        int val;

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

        /* push rc_cal value, get rc_cal value */
        ret = fc0013_writereg(priv, 0x10, 0x00);
        if (ret)
                goto error_out;

        /* get rc_cal value */
        ret = fc0013_readreg(priv, 0x10, &rc_cal);
        if (ret)
                goto error_out;

        rc_cal &= 0x0f;

        val = (int)rc_cal + rc_val;

        /* forcing rc_cal */
        ret = fc0013_writereg(priv, 0x0d, 0x11);
        if (ret)
                goto error_out;

        /* modify rc_cal value */
        if (val > 15)
                ret = fc0013_writereg(priv, 0x10, 0x0f);
        else if (val < 0)
                ret = fc0013_writereg(priv, 0x10, 0x00);
        else
                ret = fc0013_writereg(priv, 0x10, (u8)val);

error_out:
        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

        return ret;
}
EXPORT_SYMBOL(fc0013_rc_cal_add);

int fc0013_rc_cal_reset(struct dvb_frontend *fe)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        int ret;

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

        ret = fc0013_writereg(priv, 0x0d, 0x01);
        if (!ret)
                ret = fc0013_writereg(priv, 0x10, 0x00);

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

        return ret;
}
EXPORT_SYMBOL(fc0013_rc_cal_reset);

static int fc0013_set_vhf_track(struct fc0013_priv *priv, u32 freq)
{
        int ret;
        u8 tmp;

        ret = fc0013_readreg(priv, 0x1d, &tmp);
        if (ret)
                goto error_out;
        tmp &= 0xe3;
        if (freq <= 177500) {           /* VHF Track: 7 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x1c);
        } else if (freq <= 184500) {    /* VHF Track: 6 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x18);
        } else if (freq <= 191500) {    /* VHF Track: 5 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x14);
        } else if (freq <= 198500) {    /* VHF Track: 4 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x10);
        } else if (freq <= 205500) {    /* VHF Track: 3 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x0c);
        } else if (freq <= 219500) {    /* VHF Track: 2 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x08);
        } else if (freq < 300000) {     /* VHF Track: 1 */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x04);
        } else {                        /* UHF and GPS */
                ret = fc0013_writereg(priv, 0x1d, tmp | 0x1c);
        }
error_out:
        return ret;
}

static int fc0013_set_params(struct dvb_frontend *fe)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        int i, ret = 0;
        struct dtv_frontend_properties *p = &fe->dtv_property_cache;
        u32 freq = p->frequency / 1000;
        u32 delsys = p->delivery_system;
        unsigned char reg[7], am, pm, multi, tmp;
        unsigned long f_vco;
        unsigned short xtal_freq_khz_2, xin, xdiv;
        bool vco_select = false;

        if (fe->callback) {
                ret = fe->callback(priv->i2c, DVB_FRONTEND_COMPONENT_TUNER,
                        FC_FE_CALLBACK_VHF_ENABLE, (freq > 300000 ? 0 : 1));
                if (ret)
                        goto exit;
        }

        switch (priv->xtal_freq) {
        case FC_XTAL_27_MHZ:
                xtal_freq_khz_2 = 27000 / 2;
                break;
        case FC_XTAL_36_MHZ:
                xtal_freq_khz_2 = 36000 / 2;
                break;
        case FC_XTAL_28_8_MHZ:
        default:
                xtal_freq_khz_2 = 28800 / 2;
                break;
        }

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

        /* set VHF track */
        ret = fc0013_set_vhf_track(priv, freq);
        if (ret)
                goto exit;

        if (freq < 300000) {
                /* enable VHF filter */
                ret = fc0013_readreg(priv, 0x07, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x07, tmp | 0x10);
                if (ret)
                        goto exit;

                /* disable UHF & disable GPS */
                ret = fc0013_readreg(priv, 0x14, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x14, tmp & 0x1f);
                if (ret)
                        goto exit;
        } else if (freq <= 862000) {
                /* disable VHF filter */
                ret = fc0013_readreg(priv, 0x07, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x07, tmp & 0xef);
                if (ret)
                        goto exit;

                /* enable UHF & disable GPS */
                ret = fc0013_readreg(priv, 0x14, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x14, (tmp & 0x1f) | 0x40);
                if (ret)
                        goto exit;
        } else {
                /* disable VHF filter */
                ret = fc0013_readreg(priv, 0x07, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x07, tmp & 0xef);
                if (ret)
                        goto exit;

                /* disable UHF & enable GPS */
                ret = fc0013_readreg(priv, 0x14, &tmp);
                if (ret)
                        goto exit;
                ret = fc0013_writereg(priv, 0x14, (tmp & 0x1f) | 0x20);
                if (ret)
                        goto exit;
        }

        /* select frequency divider and the frequency of VCO */
        if (freq < 37084) {             /* freq * 96 < 3560000 */
                multi = 96;
                reg[5] = 0x82;
                reg[6] = 0x00;
        } else if (freq < 55625) {      /* freq * 64 < 3560000 */
                multi = 64;
                reg[5] = 0x02;
                reg[6] = 0x02;
        } else if (freq < 74167) {      /* freq * 48 < 3560000 */
                multi = 48;
                reg[5] = 0x42;
                reg[6] = 0x00;
        } else if (freq < 111250) {     /* freq * 32 < 3560000 */
                multi = 32;
                reg[5] = 0x82;
                reg[6] = 0x02;
        } else if (freq < 148334) {     /* freq * 24 < 3560000 */
                multi = 24;
                reg[5] = 0x22;
                reg[6] = 0x00;
        } else if (freq < 222500) {     /* freq * 16 < 3560000 */
                multi = 16;
                reg[5] = 0x42;
                reg[6] = 0x02;
        } else if (freq < 296667) {     /* freq * 12 < 3560000 */
                multi = 12;
                reg[5] = 0x12;
                reg[6] = 0x00;
        } else if (freq < 445000) {     /* freq * 8 < 3560000 */
                multi = 8;
                reg[5] = 0x22;
                reg[6] = 0x02;
        } else if (freq < 593334) {     /* freq * 6 < 3560000 */
                multi = 6;
                reg[5] = 0x0a;
                reg[6] = 0x00;
        } else if (freq < 950000) {     /* freq * 4 < 3800000 */
                multi = 4;
                reg[5] = 0x12;
                reg[6] = 0x02;
        } else {
                multi = 2;
                reg[5] = 0x0a;
                reg[6] = 0x02;
        }

        f_vco = freq * multi;

        if (f_vco >= 3060000) {
                reg[6] |= 0x08;
                vco_select = true;
        }

        if (freq >= 45000) {
                /* From divided value (XDIV) determined the FA and FP value */
                xdiv = (unsigned short)(f_vco / xtal_freq_khz_2);
                if ((f_vco - xdiv * xtal_freq_khz_2) >= (xtal_freq_khz_2 / 2))
                        xdiv++;

                pm = (unsigned char)(xdiv / 8);
                am = (unsigned char)(xdiv - (8 * pm));

                if (am < 2) {
                        reg[1] = am + 8;
                        reg[2] = pm - 1;
                } else {
                        reg[1] = am;
                        reg[2] = pm;
                }
        } else {
                /* fix for frequency less than 45 MHz */
                reg[1] = 0x06;
                reg[2] = 0x11;
        }

        /* fix clock out */
        reg[6] |= 0x20;

        /* From VCO frequency determines the XIN ( fractional part of Delta
           Sigma PLL) and divided value (XDIV) */
        xin = (unsigned short)(f_vco - (f_vco / xtal_freq_khz_2) * xtal_freq_khz_2);
        xin = (xin << 15) / xtal_freq_khz_2;
        if (xin >= 16384)
                xin += 32768;

        reg[3] = xin >> 8;
        reg[4] = xin & 0xff;

        if (delsys == SYS_DVBT) {
                reg[6] &= 0x3f; /* bits 6 and 7 describe the bandwidth */
                switch (p->bandwidth_hz) {
                case 6000000:
                        reg[6] |= 0x80;
                        break;
                case 7000000:
                        reg[6] |= 0x40;
                        break;
                case 8000000:
                default:
                        break;
                }
        } else {
                err("%s: modulation type not supported!", __func__);
                return -EINVAL;
        }

        /* modified for Realtek demod */
        reg[5] |= 0x07;

        for (i = 1; i <= 6; i++) {
                ret = fc0013_writereg(priv, i, reg[i]);
                if (ret)
                        goto exit;
        }

        ret = fc0013_readreg(priv, 0x11, &tmp);
        if (ret)
                goto exit;
        if (multi == 64)
                ret = fc0013_writereg(priv, 0x11, tmp | 0x04);
        else
                ret = fc0013_writereg(priv, 0x11, tmp & 0xfb);
        if (ret)
                goto exit;

        /* VCO Calibration */
        ret = fc0013_writereg(priv, 0x0e, 0x80);
        if (!ret)
                ret = fc0013_writereg(priv, 0x0e, 0x00);

        /* VCO Re-Calibration if needed */
        if (!ret)
                ret = fc0013_writereg(priv, 0x0e, 0x00);

        if (!ret) {
                msleep(10);
                ret = fc0013_readreg(priv, 0x0e, &tmp);
        }
        if (ret)
                goto exit;

        /* vco selection */
        tmp &= 0x3f;

        if (vco_select) {
                if (tmp > 0x3c) {
                        reg[6] &= ~0x08;
                        ret = fc0013_writereg(priv, 0x06, reg[6]);
                        if (!ret)
                                ret = fc0013_writereg(priv, 0x0e, 0x80);
                        if (!ret)
                                ret = fc0013_writereg(priv, 0x0e, 0x00);
                }
        } else {
                if (tmp < 0x02) {
                        reg[6] |= 0x08;
                        ret = fc0013_writereg(priv, 0x06, reg[6]);
                        if (!ret)
                                ret = fc0013_writereg(priv, 0x0e, 0x80);
                        if (!ret)
                                ret = fc0013_writereg(priv, 0x0e, 0x00);
                }
        }

        priv->frequency = p->frequency;
        priv->bandwidth = p->bandwidth_hz;

exit:
        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
        if (ret)
                warn("%s: failed: %d", __func__, ret);
        return ret;
}

static int fc0013_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        *frequency = priv->frequency;
        return 0;
}

static int fc0013_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
{
        /* always ? */
        *frequency = 0;
        return 0;
}

static int fc0013_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        *bandwidth = priv->bandwidth;
        return 0;
}

#define INPUT_ADC_LEVEL -8

static int fc0013_get_rf_strength(struct dvb_frontend *fe, u16 *strength)
{
        struct fc0013_priv *priv = fe->tuner_priv;
        int ret;
        unsigned char tmp;
        int int_temp, lna_gain, int_lna, tot_agc_gain, power;
        const int fc0013_lna_gain_table[] = {
                /* low gain */
                -63, -58, -99, -73,
                -63, -65, -54, -60,
                /* middle gain */
                 71,  70,  68,  67,
                 65,  63,  61,  58,
                /* high gain */
                197, 191, 188, 186,
                184, 182, 181, 179,
        };

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

        ret = fc0013_writereg(priv, 0x13, 0x00);
        if (ret)
                goto err;

        ret = fc0013_readreg(priv, 0x13, &tmp);
        if (ret)
                goto err;
        int_temp = tmp;

        ret = fc0013_readreg(priv, 0x14, &tmp);
        if (ret)
                goto err;
        lna_gain = tmp & 0x1f;

        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

        if (lna_gain < ARRAY_SIZE(fc0013_lna_gain_table)) {
                int_lna = fc0013_lna_gain_table[lna_gain];
                tot_agc_gain = (abs((int_temp >> 5) - 7) - 2 +
                                (int_temp & 0x1f)) * 2;
                power = INPUT_ADC_LEVEL - tot_agc_gain - int_lna / 10;

                if (power >= 45)
                        *strength = 255;        /* 100% */
                else if (power < -95)
                        *strength = 0;
                else
                        *strength = (power + 95) * 255 / 140;

                *strength |= *strength << 8;
        } else {
                ret = -1;
        }

        goto exit;

err:
        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
exit:
        if (ret)
                warn("%s: failed: %d", __func__, ret);
        return ret;
}

static const struct dvb_tuner_ops fc0013_tuner_ops = {
        .info = {
                .name           = "Fitipower FC0013",

                .frequency_min  = 37000000,     /* estimate */
                .frequency_max  = 1680000000,   /* CHECK */
                .frequency_step = 0,
        },

        .release        = fc0013_release,

        .init           = fc0013_init,
        .sleep          = fc0013_sleep,

        .set_params     = fc0013_set_params,

        .get_frequency  = fc0013_get_frequency,
        .get_if_frequency = fc0013_get_if_frequency,
        .get_bandwidth  = fc0013_get_bandwidth,

        .get_rf_strength = fc0013_get_rf_strength,
};

struct dvb_frontend *fc0013_attach(struct dvb_frontend *fe,
        struct i2c_adapter *i2c, u8 i2c_address, int dual_master,
        enum fc001x_xtal_freq xtal_freq)
{
        struct fc0013_priv *priv = NULL;

        priv = kzalloc(sizeof(struct fc0013_priv), GFP_KERNEL);
        if (priv == NULL)
                return NULL;

        priv->i2c = i2c;
        priv->dual_master = dual_master;
        priv->addr = i2c_address;
        priv->xtal_freq = xtal_freq;

        info("Fitipower FC0013 successfully attached.");

        fe->tuner_priv = priv;

        memcpy(&fe->ops.tuner_ops, &fc0013_tuner_ops,
                sizeof(struct dvb_tuner_ops));

        return fe;
}
EXPORT_SYMBOL(fc0013_attach);

MODULE_DESCRIPTION("Fitipower FC0013 silicon tuner driver");
MODULE_AUTHOR("Hans-Frieder Vogt <hfvogt@gmx.net>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.2");