tea5767.c

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/*
 * For Philips TEA5767 FM Chip used on some TV Cards like Prolink Pixelview
 * I2C address is allways 0xC0.
 *
 *
 * Copyright (c) 2005 Mauro Carvalho Chehab ([email protected])
 * This code is placed under the terms of the GNU General Public License
 *
 * tea5767 autodetection thanks to Torsten Seeboth and Atsushi Nakagawa
 * from their contributions on DScaler.
 */

#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/videodev2.h>
#include "tuner-i2c.h"
#include "tea5767.h"

static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "enable verbose debug messages");

/*****************************************************************************/

struct tea5767_priv {
    struct tuner_i2c_props  i2c_props;
    u32         frequency;
    struct tea5767_ctrl ctrl;
};

/*****************************************************************************/

/******************************
 * Write mode register values *
 ******************************/

/* First register */
#define TEA5767_MUTE        0x80    /* Mutes output */
#define TEA5767_SEARCH      0x40    /* Activates station search */
/* Bits 0-5 for divider MSB */

/* Second register */
/* Bits 0-7 for divider LSB */

/* Third register */

/* Station search from botton to up */
#define TEA5767_SEARCH_UP   0x80

/* Searches with ADC output = 10 */
#define TEA5767_SRCH_HIGH_LVL   0x60

/* Searches with ADC output = 10 */
#define TEA5767_SRCH_MID_LVL    0x40

/* Searches with ADC output = 5 */
#define TEA5767_SRCH_LOW_LVL    0x20

/* if on, div=4*(Frf+Fif)/Fref otherwise, div=4*(Frf-Fif)/Freq) */
#define TEA5767_HIGH_LO_INJECT  0x10

/* Disable stereo */
#define TEA5767_MONO        0x08

/* Disable right channel and turns to mono */
#define TEA5767_MUTE_RIGHT  0x04

/* Disable left channel and turns to mono */
#define TEA5767_MUTE_LEFT   0x02

#define TEA5767_PORT1_HIGH  0x01

/* Fourth register */
#define TEA5767_PORT2_HIGH  0x80
/* Chips stops working. Only I2C bus remains on */
#define TEA5767_STDBY       0x40

/* Japan freq (76-108 MHz. If disabled, 87.5-108 MHz */
#define TEA5767_JAPAN_BAND  0x20

/* Unselected means 32.768 KHz freq as reference. Otherwise Xtal at 13 MHz */
#define TEA5767_XTAL_32768  0x10

/* Cuts weak signals */
#define TEA5767_SOFT_MUTE   0x08

/* Activates high cut control */
#define TEA5767_HIGH_CUT_CTRL   0x04

/* Activates stereo noise control */
#define TEA5767_ST_NOISE_CTL    0x02

/* If activate PORT 1 indicates SEARCH or else it is used as PORT1 */
#define TEA5767_SRCH_IND    0x01

/* Fifth register */

/* By activating, it will use Xtal at 13 MHz as reference for divider */
#define TEA5767_PLLREF_ENABLE   0x80

/* By activating, deemphasis=50, or else, deemphasis of 50us */
#define TEA5767_DEEMPH_75   0X40

/*****************************
 * Read mode register values *
 *****************************/

/* First register */
#define TEA5767_READY_FLAG_MASK 0x80
#define TEA5767_BAND_LIMIT_MASK 0X40
/* Bits 0-5 for divider MSB after search or preset */

/* Second register */
/* Bits 0-7 for divider LSB after search or preset */

/* Third register */
#define TEA5767_STEREO_MASK 0x80
#define TEA5767_IF_CNTR_MASK    0x7f

/* Fourth register */
#define TEA5767_ADC_LEVEL_MASK  0xf0

/* should be 0 */
#define TEA5767_CHIP_ID_MASK    0x0f

/* Fifth register */
/* Reserved for future extensions */
#define TEA5767_RESERVED_MASK   0xff

/*****************************************************************************/

static void tea5767_status_dump(struct tea5767_priv *priv,
                unsigned char *buffer)
{
    unsigned int div, frq;

    if (TEA5767_READY_FLAG_MASK & buffer[0])
        tuner_info("Ready Flag ON\n");
    else
        tuner_info("Ready Flag OFF\n");

    if (TEA5767_BAND_LIMIT_MASK & buffer[0])
        tuner_info("Tuner at band limit\n");
    else
        tuner_info("Tuner not at band limit\n");

    div = ((buffer[0] & 0x3f) << 8) | buffer[1];

    switch (priv->ctrl.xtal_freq) {
    case TEA5767_HIGH_LO_13MHz:
        frq = (div * 50000 - 700000 - 225000) / 4;  /* Freq in KHz */
        break;
    case TEA5767_LOW_LO_13MHz:
        frq = (div * 50000 + 700000 + 225000) / 4;  /* Freq in KHz */
        break;
    case TEA5767_LOW_LO_32768:
        frq = (div * 32768 + 700000 + 225000) / 4;  /* Freq in KHz */
        break;
    case TEA5767_HIGH_LO_32768:
    default:
        frq = (div * 32768 - 700000 - 225000) / 4;  /* Freq in KHz */
        break;
    }
    buffer[0] = (div >> 8) & 0x3f;
    buffer[1] = div & 0xff;

    tuner_info("Frequency %d.%03d KHz (divider = 0x%04x)\n",
           frq / 1000, frq % 1000, div);

    if (TEA5767_STEREO_MASK & buffer[2])
        tuner_info("Stereo\n");
    else
        tuner_info("Mono\n");

    tuner_info("IF Counter = %d\n", buffer[2] & TEA5767_IF_CNTR_MASK);

    tuner_info("ADC Level = %d\n",
           (buffer[3] & TEA5767_ADC_LEVEL_MASK) >> 4);

    tuner_info("Chip ID = %d\n", (buffer[3] & TEA5767_CHIP_ID_MASK));

    tuner_info("Reserved = 0x%02x\n",
           (buffer[4] & TEA5767_RESERVED_MASK));
}

/* Freq should be specifyed at 62.5 Hz */
static int set_radio_freq(struct dvb_frontend *fe,
              struct analog_parameters *params)
{
    struct tea5767_priv *priv = fe->tuner_priv;
    unsigned int frq = params->frequency;
    unsigned char buffer[5];
    unsigned div;
    int rc;

    tuner_dbg("radio freq = %d.%03d MHz\n", frq/16000,(frq/16)%1000);

    buffer[2] = 0;

    if (priv->ctrl.port1)
        buffer[2] |= TEA5767_PORT1_HIGH;

    if (params->audmode == V4L2_TUNER_MODE_MONO) {
        tuner_dbg("TEA5767 set to mono\n");
        buffer[2] |= TEA5767_MONO;
    } else {
        tuner_dbg("TEA5767 set to stereo\n");
    }


    buffer[3] = 0;

    if (priv->ctrl.port2)
        buffer[3] |= TEA5767_PORT2_HIGH;

    if (priv->ctrl.high_cut)
        buffer[3] |= TEA5767_HIGH_CUT_CTRL;

    if (priv->ctrl.st_noise)
        buffer[3] |= TEA5767_ST_NOISE_CTL;

    if (priv->ctrl.soft_mute)
        buffer[3] |= TEA5767_SOFT_MUTE;

    if (priv->ctrl.japan_band)
        buffer[3] |= TEA5767_JAPAN_BAND;

    buffer[4] = 0;

    if (priv->ctrl.deemph_75)
        buffer[4] |= TEA5767_DEEMPH_75;

    if (priv->ctrl.pllref)
        buffer[4] |= TEA5767_PLLREF_ENABLE;


    /* Rounds freq to next decimal value - for 62.5 KHz step */
    /* frq = 20*(frq/16)+radio_frq[frq%16]; */

    switch (priv->ctrl.xtal_freq) {
    case TEA5767_HIGH_LO_13MHz:
        tuner_dbg("radio HIGH LO inject xtal @ 13 MHz\n");
        buffer[2] |= TEA5767_HIGH_LO_INJECT;
        div = (frq * (4000 / 16) + 700000 + 225000 + 25000) / 50000;
        break;
    case TEA5767_LOW_LO_13MHz:
        tuner_dbg("radio LOW LO inject xtal @ 13 MHz\n");

        div = (frq * (4000 / 16) - 700000 - 225000 + 25000) / 50000;
        break;
    case TEA5767_LOW_LO_32768:
        tuner_dbg("radio LOW LO inject xtal @ 32,768 MHz\n");
        buffer[3] |= TEA5767_XTAL_32768;
        /* const 700=4000*175 Khz - to adjust freq to right value */
        div = ((frq * (4000 / 16) - 700000 - 225000) + 16384) >> 15;
        break;
    case TEA5767_HIGH_LO_32768:
    default:
        tuner_dbg("radio HIGH LO inject xtal @ 32,768 MHz\n");

        buffer[2] |= TEA5767_HIGH_LO_INJECT;
        buffer[3] |= TEA5767_XTAL_32768;
        div = ((frq * (4000 / 16) + 700000 + 225000) + 16384) >> 15;
        break;
    }
    buffer[0] = (div >> 8) & 0x3f;
    buffer[1] = div & 0xff;

    if (5 != (rc = tuner_i2c_xfer_send(&priv->i2c_props, buffer, 5)))
        tuner_warn("i2c i/o error: rc == %d (should be 5)\n", rc);

    if (debug) {
        if (5 != (rc = tuner_i2c_xfer_recv(&priv->i2c_props, buffer, 5)))
            tuner_warn("i2c i/o error: rc == %d (should be 5)\n", rc);
        else
            tea5767_status_dump(priv, buffer);
    }

    priv->frequency = frq * 125 / 2;

    return 0;
}

static int tea5767_read_status(struct dvb_frontend *fe, char *buffer)
{
    struct tea5767_priv *priv = fe->tuner_priv;
    int rc;

    memset(buffer, 0, 5);
    if (5 != (rc = tuner_i2c_xfer_recv(&priv->i2c_props, buffer, 5))) {
        tuner_warn("i2c i/o error: rc == %d (should be 5)\n", rc);
        return -EREMOTEIO;
    }

    return 0;
}

static inline int tea5767_signal(struct dvb_frontend *fe, const char *buffer)
{
    struct tea5767_priv *priv = fe->tuner_priv;

    int signal = ((buffer[3] & TEA5767_ADC_LEVEL_MASK) << 8);

    tuner_dbg("Signal strength: %d\n", signal);

    return signal;
}

static inline int tea5767_stereo(struct dvb_frontend *fe, const char *buffer)
{
    struct tea5767_priv *priv = fe->tuner_priv;

    int stereo = buffer[2] & TEA5767_STEREO_MASK;

    tuner_dbg("Radio ST GET = %02x\n", stereo);

    return (stereo ? V4L2_TUNER_SUB_STEREO : 0);
}

static int tea5767_get_status(struct dvb_frontend *fe, u32 *status)
{
    unsigned char buffer[5];

    *status = 0;

    if (0 == tea5767_read_status(fe, buffer)) {
        if (tea5767_signal(fe, buffer))
            *status = TUNER_STATUS_LOCKED;
        if (tea5767_stereo(fe, buffer))
            *status |= TUNER_STATUS_STEREO;
    }

    return 0;
}

static int tea5767_get_rf_strength(struct dvb_frontend *fe, u16 *strength)
{
    unsigned char buffer[5];

    *strength = 0;

    if (0 == tea5767_read_status(fe, buffer))
        *strength = tea5767_signal(fe, buffer);

    return 0;
}

static int tea5767_standby(struct dvb_frontend *fe)
{
    unsigned char buffer[5];
    struct tea5767_priv *priv = fe->tuner_priv;
    unsigned div, rc;

    div = (87500 * 4 + 700 + 225 + 25) / 50; /* Set frequency to 87.5 MHz */
    buffer[0] = (div >> 8) & 0x3f;
    buffer[1] = div & 0xff;
    buffer[2] = TEA5767_PORT1_HIGH;
    buffer[3] = TEA5767_PORT2_HIGH | TEA5767_HIGH_CUT_CTRL |
            TEA5767_ST_NOISE_CTL | TEA5767_JAPAN_BAND | TEA5767_STDBY;
    buffer[4] = 0;

    if (5 != (rc = tuner_i2c_xfer_send(&priv->i2c_props, buffer, 5)))
        tuner_warn("i2c i/o error: rc == %d (should be 5)\n", rc);

    return 0;
}

int tea5767_autodetection(struct i2c_adapter* i2c_adap, u8 i2c_addr)
{
    struct tuner_i2c_props i2c = { .adap = i2c_adap, .addr = i2c_addr };
    unsigned char buffer[7] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    int rc;

    if ((rc = tuner_i2c_xfer_recv(&i2c, buffer, 7))< 5) {
        printk(KERN_WARNING "It is not a TEA5767. Received %i bytes.\n", rc);
        return -EINVAL;
    }

    /* If all bytes are the same then it's a TV tuner and not a tea5767 */
    if (buffer[0] == buffer[1] && buffer[0] == buffer[2] &&
        buffer[0] == buffer[3] && buffer[0] == buffer[4]) {
        printk(KERN_WARNING "All bytes are equal. It is not a TEA5767\n");
        return -EINVAL;
    }

    /*  Status bytes:
     *  Byte 4: bit 3:1 : CI (Chip Identification) == 0
     *          bit 0   : internally set to 0
     *  Byte 5: bit 7:0 : == 0
     */
    if (((buffer[3] & 0x0f) != 0x00) || (buffer[4] != 0x00)) {
        printk(KERN_WARNING "Chip ID is not zero. It is not a TEA5767\n");
        return -EINVAL;
    }


    return 0;
}

static int tea5767_release(struct dvb_frontend *fe)
{
    kfree(fe->tuner_priv);
    fe->tuner_priv = NULL;

    return 0;
}

static int tea5767_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
    struct tea5767_priv *priv = fe->tuner_priv;
    *frequency = priv->frequency;

    return 0;
}

static int tea5767_set_config (struct dvb_frontend *fe, void *priv_cfg)
{
    struct tea5767_priv *priv = fe->tuner_priv;

    memcpy(&priv->ctrl, priv_cfg, sizeof(priv->ctrl));

    return 0;
}

static struct dvb_tuner_ops tea5767_tuner_ops = {
    .info = {
        .name           = "tea5767", // Philips TEA5767HN FM Radio
    },

    .set_analog_params = set_radio_freq,
    .set_config    = tea5767_set_config,
    .sleep             = tea5767_standby,
    .release           = tea5767_release,
    .get_frequency     = tea5767_get_frequency,
    .get_status        = tea5767_get_status,
    .get_rf_strength   = tea5767_get_rf_strength,
};

struct dvb_frontend *tea5767_attach(struct dvb_frontend *fe,
                    struct i2c_adapter* i2c_adap,
                    u8 i2c_addr)
{
    struct tea5767_priv *priv = NULL;

    priv = kzalloc(sizeof(struct tea5767_priv), GFP_KERNEL);
    if (priv == NULL)
        return NULL;
    fe->tuner_priv = priv;

    priv->i2c_props.addr  = i2c_addr;
    priv->i2c_props.adap  = i2c_adap;
    priv->i2c_props.name  = "tea5767";

    priv->ctrl.xtal_freq  = TEA5767_HIGH_LO_32768;
    priv->ctrl.port1      = 1;
    priv->ctrl.port2      = 1;
    priv->ctrl.high_cut   = 1;
    priv->ctrl.st_noise   = 1;
    priv->ctrl.japan_band = 1;

    memcpy(&fe->ops.tuner_ops, &tea5767_tuner_ops,
           sizeof(struct dvb_tuner_ops));

    tuner_info("type set to %s\n", "Philips TEA5767HN FM Radio");

    return fe;
}

EXPORT_SYMBOL_GPL(tea5767_attach);
EXPORT_SYMBOL_GPL(tea5767_autodetection);

MODULE_DESCRIPTION("Philips TEA5767 FM tuner driver");
MODULE_AUTHOR("Mauro Carvalho Chehab <[email protected]>");
MODULE_LICENSE("GPL");