// SPDX-License-Identifier: GPL-2.0
// For Philips TEA5767 FM Chip used on some TV Cards like Prolink Pixelview
// I2C address is always 0xC0.
//
// Copyright (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org>
//
// tea5767 autodetection thanks to Torsten Seeboth and Atsushi Nakagawa
// from their contributions on DScaler.

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#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 bottom 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 specified 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) {
                pr_warn("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]) {
                pr_warn("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)) {
                pr_warn("Chip ID is not zero. It is not a TEA5767\n");
                return -EINVAL;
        }


        return 0;
}

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

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 const 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_obj(struct tea5767_priv);
        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 <mchehab@kernel.org>");
MODULE_LICENSE("GPL v2");