tea5761.c

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/*
 * For Philips TEA5761 FM Chip
 * I2C address is allways 0x20 (0x10 at 7-bit mode).
 *
 * Copyright (c) 2005-2007 Mauro Carvalho Chehab ([email protected])
 * This code is placed under the terms of the GNUv2 General Public License
 *
 */

#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/videodev2.h>
#include <media/tuner.h>
#include "tuner-i2c.h"
#include "tea5761.h"

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

struct tea5761_priv {
    struct tuner_i2c_props i2c_props;

    u32 frequency;
    bool standby;
};

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

/***************************
 * TEA5761HN I2C registers *
 ***************************/

/* INTREG - Read: bytes 0 and 1 / Write: byte 0 */

    /* first byte for reading */
#define TEA5761_INTREG_IFFLAG       0x10
#define TEA5761_INTREG_LEVFLAG      0x8
#define TEA5761_INTREG_FRRFLAG      0x2
#define TEA5761_INTREG_BLFLAG       0x1

    /* second byte for reading / byte for writing */
#define TEA5761_INTREG_IFMSK        0x10
#define TEA5761_INTREG_LEVMSK       0x8
#define TEA5761_INTREG_FRMSK        0x2
#define TEA5761_INTREG_BLMSK        0x1

/* FRQSET - Read: bytes 2 and 3 / Write: byte 1 and 2 */

    /* First byte */
#define TEA5761_FRQSET_SEARCH_UP 0x80       /* 1=Station search from botton to up */
#define TEA5761_FRQSET_SEARCH_MODE 0x40     /* 1=Search mode */

    /* Bits 0-5 for divider MSB */

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

/* TNCTRL - Read: bytes 4 and 5 / Write: Bytes 3 and 4 */

    /* first byte */

#define TEA5761_TNCTRL_PUPD_0   0x40    /* Power UP/Power Down MSB */
#define TEA5761_TNCTRL_BLIM 0X20    /* 1= Japan Frequencies, 0= European frequencies */
#define TEA5761_TNCTRL_SWPM 0x10    /* 1= software port is FRRFLAG */
#define TEA5761_TNCTRL_IFCTC    0x08    /* 1= IF count time 15.02 ms, 0= IF count time 2.02 ms */
#define TEA5761_TNCTRL_AFM  0x04
#define TEA5761_TNCTRL_SMUTE    0x02    /* 1= Soft mute */
#define TEA5761_TNCTRL_SNC  0x01

    /* second byte */

#define TEA5761_TNCTRL_MU   0x80    /* 1=Hard mute */
#define TEA5761_TNCTRL_SSL_1    0x40
#define TEA5761_TNCTRL_SSL_0    0x20
#define TEA5761_TNCTRL_HLSI 0x10
#define TEA5761_TNCTRL_MST  0x08    /* 1 = mono */
#define TEA5761_TNCTRL_SWP  0x04
#define TEA5761_TNCTRL_DTC  0x02    /* 1 = deemphasis 50 us, 0 = deemphasis 75 us */
#define TEA5761_TNCTRL_AHLSI    0x01

/* FRQCHECK - Read: bytes 6 and 7  */
    /* First byte */

    /* Bits 0-5 for divider MSB */

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

/* TUNCHECK - Read: bytes 8 and 9  */

    /* First byte */
#define TEA5761_TUNCHECK_IF_MASK    0x7e    /* IF count */
#define TEA5761_TUNCHECK_TUNTO      0x01

    /* Second byte */
#define TEA5761_TUNCHECK_LEV_MASK   0xf0    /* Level Count */
#define TEA5761_TUNCHECK_LD     0x08
#define TEA5761_TUNCHECK_STEREO     0x04

/* TESTREG - Read: bytes 10 and 11 / Write: bytes 5 and 6 */

    /* All zero = no test mode */

/* MANID - Read: bytes 12 and 13 */

    /* First byte - should be 0x10 */
#define TEA5767_MANID_VERSION_MASK  0xf0    /* Version = 1 */
#define TEA5767_MANID_ID_MSB_MASK   0x0f    /* Manufacurer ID - should be 0 */

    /* Second byte - Should be 0x2b */

#define TEA5767_MANID_ID_LSB_MASK   0xfe    /* Manufacturer ID - should be 0x15 */
#define TEA5767_MANID_IDAV      0x01    /* 1 = Chip has ID, 0 = Chip has no ID */

/* Chip ID - Read: bytes 14 and 15 */

    /* First byte - should be 0x57 */

    /* Second byte - should be 0x61 */

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

#define FREQ_OFFSET 0 /* for TEA5767, it is 700 to give the right freq */
static void tea5761_status_dump(unsigned char *buffer)
{
    unsigned int div, frq;

    div = ((buffer[2] & 0x3f) << 8) | buffer[3];

    frq = 1000 * (div * 32768 / 1000 + FREQ_OFFSET + 225) / 4;  /* Freq in KHz */

    printk(KERN_INFO "tea5761: Frequency %d.%03d KHz (divider = 0x%04x)\n",
           frq / 1000, frq % 1000, div);
}

/* Freq should be specifyed at 62.5 Hz */
static int __set_radio_freq(struct dvb_frontend *fe,
                unsigned int freq,
                bool mono)
{
    struct tea5761_priv *priv = fe->tuner_priv;
    unsigned int frq = freq;
    unsigned char buffer[7] = {0, 0, 0, 0, 0, 0, 0 };
    unsigned div;
    int rc;

    tuner_dbg("radio freq counter %d\n", frq);

    if (priv->standby) {
        tuner_dbg("TEA5761 set to standby mode\n");
        buffer[5] |= TEA5761_TNCTRL_MU;
    } else {
        buffer[4] |= TEA5761_TNCTRL_PUPD_0;
    }


    if (mono) {
        tuner_dbg("TEA5761 set to mono\n");
        buffer[5] |= TEA5761_TNCTRL_MST;
    } else {
        tuner_dbg("TEA5761 set to stereo\n");
    }

    div = (1000 * (frq * 4 / 16 + 700 + 225) ) >> 15;
    buffer[1] = (div >> 8) & 0x3f;
    buffer[2] = div & 0xff;

    if (debug)
        tea5761_status_dump(buffer);

    if (7 != (rc = tuner_i2c_xfer_send(&priv->i2c_props, buffer, 7)))
        tuner_warn("i2c i/o error: rc == %d (should be 5)\n", rc);

    priv->frequency = frq * 125 / 2;

    return 0;
}

static int set_radio_freq(struct dvb_frontend *fe,
              struct analog_parameters *params)
{
    struct tea5761_priv *priv = fe->analog_demod_priv;

    priv->standby = false;

    return __set_radio_freq(fe, params->frequency,
                params->audmode == V4L2_TUNER_MODE_MONO);
}

static int set_radio_sleep(struct dvb_frontend *fe)
{
    struct tea5761_priv *priv = fe->analog_demod_priv;

    priv->standby = true;

    return __set_radio_freq(fe, priv->frequency, false);
}

static int tea5761_read_status(struct dvb_frontend *fe, char *buffer)
{
    struct tea5761_priv *priv = fe->tuner_priv;
    int rc;

    memset(buffer, 0, 16);
    if (16 != (rc = tuner_i2c_xfer_recv(&priv->i2c_props, buffer, 16))) {
        tuner_warn("i2c i/o error: rc == %d (should be 16)\n", rc);
        return -EREMOTEIO;
    }

    return 0;
}

static inline int tea5761_signal(struct dvb_frontend *fe, const char *buffer)
{
    struct tea5761_priv *priv = fe->tuner_priv;

    int signal = ((buffer[9] & TEA5761_TUNCHECK_LEV_MASK) << (13 - 4));

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

    return signal;
}

static inline int tea5761_stereo(struct dvb_frontend *fe, const char *buffer)
{
    struct tea5761_priv *priv = fe->tuner_priv;

    int stereo = buffer[9] & TEA5761_TUNCHECK_STEREO;

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

    return (stereo ? V4L2_TUNER_SUB_STEREO : 0);
}

static int tea5761_get_status(struct dvb_frontend *fe, u32 *status)
{
    unsigned char buffer[16];

    *status = 0;

    if (0 == tea5761_read_status(fe, buffer)) {
        if (tea5761_signal(fe, buffer))
            *status = TUNER_STATUS_LOCKED;
        if (tea5761_stereo(fe, buffer))
            *status |= TUNER_STATUS_STEREO;
    }

    return 0;
}

static int tea5761_get_rf_strength(struct dvb_frontend *fe, u16 *strength)
{
    unsigned char buffer[16];

    *strength = 0;

    if (0 == tea5761_read_status(fe, buffer))
        *strength = tea5761_signal(fe, buffer);

    return 0;
}

int tea5761_autodetection(struct i2c_adapter* i2c_adap, u8 i2c_addr)
{
    unsigned char buffer[16];
    int rc;
    struct tuner_i2c_props i2c = { .adap = i2c_adap, .addr = i2c_addr };

    if (16 != (rc = tuner_i2c_xfer_recv(&i2c, buffer, 16))) {
        printk(KERN_WARNING "it is not a TEA5761. Received %i chars.\n", rc);
        return -EINVAL;
    }

    if ((buffer[13] != 0x2b) || (buffer[14] != 0x57) || (buffer[15] != 0x061)) {
        printk(KERN_WARNING "Manufacturer ID= 0x%02x, Chip ID = %02x%02x."
                    " It is not a TEA5761\n",
                    buffer[13], buffer[14], buffer[15]);
        return -EINVAL;
    }
    printk(KERN_WARNING "tea5761: TEA%02x%02x detected. "
                "Manufacturer ID= 0x%02x\n",
                buffer[14], buffer[15], buffer[13]);

    return 0;
}

static int tea5761_release(struct dvb_frontend *fe)
{
    kfree(fe->tuner_priv);
    fe->tuner_priv = NULL;

    return 0;
}

static int tea5761_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
    struct tea5761_priv *priv = fe->tuner_priv;
    *frequency = priv->frequency;
    return 0;
}

static struct dvb_tuner_ops tea5761_tuner_ops = {
    .info = {
        .name           = "tea5761", // Philips TEA5761HN FM Radio
    },
    .set_analog_params = set_radio_freq,
    .sleep         = set_radio_sleep,
    .release           = tea5761_release,
    .get_frequency     = tea5761_get_frequency,
    .get_status        = tea5761_get_status,
    .get_rf_strength   = tea5761_get_rf_strength,
};

struct dvb_frontend *tea5761_attach(struct dvb_frontend *fe,
                    struct i2c_adapter* i2c_adap,
                    u8 i2c_addr)
{
    struct tea5761_priv *priv = NULL;

    if (tea5761_autodetection(i2c_adap, i2c_addr) != 0)
        return NULL;

    priv = kzalloc(sizeof(struct tea5761_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 = "tea5761";

    memcpy(&fe->ops.tuner_ops, &tea5761_tuner_ops,
           sizeof(struct dvb_tuner_ops));

    tuner_info("type set to %s\n", "Philips TEA5761HN FM Radio");

    return fe;
}


EXPORT_SYMBOL_GPL(tea5761_attach);
EXPORT_SYMBOL_GPL(tea5761_autodetection);

MODULE_DESCRIPTION("Philips TEA5761 FM tuner driver");
MODULE_AUTHOR("Mauro Carvalho Chehab <[email protected]>");
MODULE_LICENSE("GPL");