// SPDX-License-Identifier: GPL-2.0
// For Philips TEA5761 FM Chip
// I2C address is always 0x20 (0x10 at 7-bit mode).
//
// Copyright (c) 2005-2007 Mauro Carvalho Chehab <mchehab@kernel.org>

#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 bottom 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 specified 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 void tea5761_release(struct dvb_frontend *fe)
{
        kfree(fe->tuner_priv);
        fe->tuner_priv = NULL;
}

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

static const 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_obj(struct tea5761_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 = "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 <mchehab@kernel.org>");
MODULE_LICENSE("GPL v2");