tda18218.c

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/*
 * NXP TDA18218HN silicon tuner driver
 *
 * Copyright (C) 2010 Antti Palosaari <[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 "tda18218_priv.h"

/* write multiple registers */
static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
{
    int ret = 0, len2, remaining;
    u8 buf[1 + len];
    struct i2c_msg msg[1] = {
        {
            .addr = priv->cfg->i2c_address,
            .flags = 0,
            .buf = buf,
        }
    };

    for (remaining = len; remaining > 0;
            remaining -= (priv->cfg->i2c_wr_max - 1)) {
        len2 = remaining;
        if (len2 > (priv->cfg->i2c_wr_max - 1))
            len2 = (priv->cfg->i2c_wr_max - 1);

        msg[0].len = 1 + len2;
        buf[0] = reg + len - remaining;
        memcpy(&buf[1], &val[len - remaining], len2);

        ret = i2c_transfer(priv->i2c, msg, 1);
        if (ret != 1)
            break;
    }

    if (ret == 1) {
        ret = 0;
    } else {
        dev_warn(&priv->i2c->dev, "%s: i2c wr failed=%d reg=%02x " \
                "len=%d\n", KBUILD_MODNAME, ret, reg, len);
        ret = -EREMOTEIO;
    }

    return ret;
}

/* read multiple registers */
static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
{
    int ret;
    u8 buf[reg+len]; /* we must start read always from reg 0x00 */
    struct i2c_msg msg[2] = {
        {
            .addr = priv->cfg->i2c_address,
            .flags = 0,
            .len = 1,
            .buf = "\x00",
        }, {
            .addr = priv->cfg->i2c_address,
            .flags = I2C_M_RD,
            .len = sizeof(buf),
            .buf = buf,
        }
    };

    ret = i2c_transfer(priv->i2c, msg, 2);
    if (ret == 2) {
        memcpy(val, &buf[reg], len);
        ret = 0;
    } else {
        dev_warn(&priv->i2c->dev, "%s: i2c rd failed=%d reg=%02x " \
                "len=%d\n", KBUILD_MODNAME, ret, reg, len);
        ret = -EREMOTEIO;
    }

    return ret;
}

/* write single register */
static int tda18218_wr_reg(struct tda18218_priv *priv, u8 reg, u8 val)
{
    return tda18218_wr_regs(priv, reg, &val, 1);
}

/* read single register */

static int tda18218_rd_reg(struct tda18218_priv *priv, u8 reg, u8 *val)
{
    return tda18218_rd_regs(priv, reg, val, 1);
}

static int tda18218_set_params(struct dvb_frontend *fe)
{
    struct tda18218_priv *priv = fe->tuner_priv;
    struct dtv_frontend_properties *c = &fe->dtv_property_cache;
    u32 bw = c->bandwidth_hz;
    int ret;
    u8 buf[3], i, BP_Filter, LP_Fc;
    u32 LO_Frac;
    /* TODO: find out correct AGC algorithm */
    u8 agc[][2] = {
        { R20_AGC11, 0x60 },
        { R23_AGC21, 0x02 },
        { R20_AGC11, 0xa0 },
        { R23_AGC21, 0x09 },
        { R20_AGC11, 0xe0 },
        { R23_AGC21, 0x0c },
        { R20_AGC11, 0x40 },
        { R23_AGC21, 0x01 },
        { R20_AGC11, 0x80 },
        { R23_AGC21, 0x08 },
        { R20_AGC11, 0xc0 },
        { R23_AGC21, 0x0b },
        { R24_AGC22, 0x1c },
        { R24_AGC22, 0x0c },
    };

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

    /* low-pass filter cut-off frequency */
    if (bw <= 6000000) {
        LP_Fc = 0;
        priv->if_frequency = 3000000;
    } else if (bw <= 7000000) {
        LP_Fc = 1;
        priv->if_frequency = 3500000;
    } else {
        LP_Fc = 2;
        priv->if_frequency = 4000000;
    }

    LO_Frac = c->frequency + priv->if_frequency;

    /* band-pass filter */
    if (LO_Frac < 188000000)
        BP_Filter = 3;
    else if (LO_Frac < 253000000)
        BP_Filter = 4;
    else if (LO_Frac < 343000000)
        BP_Filter = 5;
    else
        BP_Filter = 6;

    buf[0] = (priv->regs[R1A_IF1] & ~7) | BP_Filter; /* BP_Filter */
    buf[1] = (priv->regs[R1B_IF2] & ~3) | LP_Fc; /* LP_Fc */
    buf[2] = priv->regs[R1C_AGC2B];
    ret = tda18218_wr_regs(priv, R1A_IF1, buf, 3);
    if (ret)
        goto error;

    buf[0] = (LO_Frac / 1000) >> 12; /* LO_Frac_0 */
    buf[1] = (LO_Frac / 1000) >> 4; /* LO_Frac_1 */
    buf[2] = (LO_Frac / 1000) << 4 |
        (priv->regs[R0C_MD5] & 0x0f); /* LO_Frac_2 */
    ret = tda18218_wr_regs(priv, R0A_MD3, buf, 3);
    if (ret)
        goto error;

    buf[0] = priv->regs[R0F_MD8] | (1 << 6); /* Freq_prog_Start */
    ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
    if (ret)
        goto error;

    buf[0] = priv->regs[R0F_MD8] & ~(1 << 6); /* Freq_prog_Start */
    ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
    if (ret)
        goto error;

    /* trigger AGC */
    for (i = 0; i < ARRAY_SIZE(agc); i++) {
        ret = tda18218_wr_reg(priv, agc[i][0], agc[i][1]);
        if (ret)
            goto error;
    }

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

    if (ret)
        dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

    return ret;
}

static int tda18218_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
{
    struct tda18218_priv *priv = fe->tuner_priv;
    *frequency = priv->if_frequency;
    dev_dbg(&priv->i2c->dev, "%s: if_frequency=%d\n", __func__, *frequency);
    return 0;
}

static int tda18218_sleep(struct dvb_frontend *fe)
{
    struct tda18218_priv *priv = fe->tuner_priv;
    int ret;

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

    /* standby */
    ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));

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

    if (ret)
        dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

    return ret;
}

static int tda18218_init(struct dvb_frontend *fe)
{
    struct tda18218_priv *priv = fe->tuner_priv;
    int ret;

    /* TODO: calibrations */

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

    ret = tda18218_wr_regs(priv, R00_ID, priv->regs, TDA18218_NUM_REGS);

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

    if (ret)
        dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

    return ret;
}

static int tda18218_release(struct dvb_frontend *fe)
{
    kfree(fe->tuner_priv);
    fe->tuner_priv = NULL;
    return 0;
}

static const struct dvb_tuner_ops tda18218_tuner_ops = {
    .info = {
        .name           = "NXP TDA18218",

        .frequency_min  = 174000000,
        .frequency_max  = 864000000,
        .frequency_step =      1000,
    },

    .release       = tda18218_release,
    .init          = tda18218_init,
    .sleep         = tda18218_sleep,

    .set_params    = tda18218_set_params,

    .get_if_frequency = tda18218_get_if_frequency,
};

struct dvb_frontend *tda18218_attach(struct dvb_frontend *fe,
    struct i2c_adapter *i2c, struct tda18218_config *cfg)
{
    struct tda18218_priv *priv = NULL;
    u8 uninitialized_var(val);
    int ret;
    /* chip default registers values */
    static u8 def_regs[] = {
        0xc0, 0x88, 0x00, 0x8e, 0x03, 0x00, 0x00, 0xd0, 0x00, 0x40,
        0x00, 0x00, 0x07, 0xff, 0x84, 0x09, 0x00, 0x13, 0x00, 0x00,
        0x01, 0x84, 0x09, 0xf0, 0x19, 0x0a, 0x8e, 0x69, 0x98, 0x01,
        0x00, 0x58, 0x10, 0x40, 0x8c, 0x00, 0x0c, 0x48, 0x85, 0xc9,
        0xa7, 0x00, 0x00, 0x00, 0x30, 0x81, 0x80, 0x00, 0x39, 0x00,
        0x8a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf6, 0xf6
    };

    priv = kzalloc(sizeof(struct tda18218_priv), GFP_KERNEL);
    if (priv == NULL)
        return NULL;

    priv->cfg = cfg;
    priv->i2c = i2c;
    fe->tuner_priv = priv;

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

    /* check if the tuner is there */
    ret = tda18218_rd_reg(priv, R00_ID, &val);
    dev_dbg(&priv->i2c->dev, "%s: ret=%d chip id=%02x\n", __func__, ret,
            val);
    if (ret || val != def_regs[R00_ID]) {
        kfree(priv);
        return NULL;
    }

    dev_info(&priv->i2c->dev,
            "%s: NXP TDA18218HN successfully identified\n",
            KBUILD_MODNAME);

    memcpy(&fe->ops.tuner_ops, &tda18218_tuner_ops,
        sizeof(struct dvb_tuner_ops));
    memcpy(priv->regs, def_regs, sizeof(def_regs));

    /* loop-through enabled chip default register values */
    if (priv->cfg->loop_through) {
        priv->regs[R17_PD1] = 0xb0;
        priv->regs[R18_PD2] = 0x59;
    }

    /* standby */
    ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));
    if (ret)
        dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

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

    return fe;
}
EXPORT_SYMBOL(tda18218_attach);

MODULE_DESCRIPTION("NXP TDA18218HN silicon tuner driver");
MODULE_AUTHOR("Antti Palosaari <[email protected]>");
MODULE_LICENSE("GPL");