// SPDX-License-Identifier: GPL-2.0-or-later
/*
        STV6110(A) Silicon tuner driver

        Copyright (C) Manu Abraham <abraham.manu@gmail.com>

        Copyright (C) ST Microelectronics

*/

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <media/dvb_frontend.h>

#include "stv6110x_reg.h"
#include "stv6110x.h"
#include "stv6110x_priv.h"

/* Max transfer size done by I2C transfer functions */
#define MAX_XFER_SIZE  64

static unsigned int verbose;
module_param(verbose, int, 0644);
MODULE_PARM_DESC(verbose, "Set Verbosity level");

static int stv6110x_read_reg(struct stv6110x_state *stv6110x, u8 reg, u8 *data)
{
        int ret;
        const struct stv6110x_config *config = stv6110x->config;
        u8 b0[] = { reg };
        u8 b1[] = { 0 };
        struct i2c_msg msg[] = {
                { .addr = config->addr, .flags = 0,        .buf = b0, .len = 1 },
                { .addr = config->addr, .flags = I2C_M_RD, .buf = b1, .len = 1 }
        };

        ret = i2c_transfer(stv6110x->i2c, msg, 2);
        if (ret != 2) {
                dprintk(FE_ERROR, 1, "I/O Error");
                return -EREMOTEIO;
        }
        *data = b1[0];

        return 0;
}

static int stv6110x_write_regs(struct stv6110x_state *stv6110x, int start, u8 data[], int len)
{
        int ret;
        const struct stv6110x_config *config = stv6110x->config;
        u8 buf[MAX_XFER_SIZE];

        struct i2c_msg msg = {
                .addr = config->addr,
                .flags = 0,
                .buf = buf,
                .len = len + 1
        };

        if (1 + len > sizeof(buf)) {
                printk(KERN_WARNING
                       "%s: i2c wr: len=%d is too big!\n",
                       KBUILD_MODNAME, len);
                return -EINVAL;
        }

        if (start + len > 8)
                return -EINVAL;

        buf[0] = start;
        memcpy(&buf[1], data, len);

        ret = i2c_transfer(stv6110x->i2c, &msg, 1);
        if (ret != 1) {
                dprintk(FE_ERROR, 1, "I/O Error");
                return -EREMOTEIO;
        }

        return 0;
}

static int stv6110x_write_reg(struct stv6110x_state *stv6110x, u8 reg, u8 data)
{
        u8 tmp = data; /* see gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */

        return stv6110x_write_regs(stv6110x, reg, &tmp, 1);
}

static int stv6110x_init(struct dvb_frontend *fe)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;
        int ret;

        ret = stv6110x_write_regs(stv6110x, 0, stv6110x->regs,
                                  ARRAY_SIZE(stv6110x->regs));
        if (ret < 0) {
                dprintk(FE_ERROR, 1, "Initialization failed");
                return -1;
        }

        return 0;
}

static int stv6110x_set_frequency(struct dvb_frontend *fe, u32 frequency)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;
        u32 rDiv, divider;
        s32 pVal, pCalc, rDivOpt = 0, pCalcOpt = 1000;
        u8 i;

        STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_K, (REFCLOCK_MHz - 16));

        if (frequency <= 1023000) {
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_DIV4SEL, 1);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_PRESC32_ON, 0);
                pVal = 40;
        } else if (frequency <= 1300000) {
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_DIV4SEL, 1);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_PRESC32_ON, 1);
                pVal = 40;
        } else if (frequency <= 2046000) {
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_DIV4SEL, 0);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_PRESC32_ON, 0);
                pVal = 20;
        } else {
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_DIV4SEL, 0);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_PRESC32_ON, 1);
                pVal = 20;
        }

        for (rDiv = 0; rDiv <= 3; rDiv++) {
                pCalc = (REFCLOCK_kHz / 100) / R_DIV(rDiv);

                if ((abs((s32)(pCalc - pVal))) < (abs((s32)(pCalcOpt - pVal))))
                        rDivOpt = rDiv;

                pCalcOpt = (REFCLOCK_kHz / 100) / R_DIV(rDivOpt);
        }

        divider = (frequency * R_DIV(rDivOpt) * pVal) / REFCLOCK_kHz;
        divider = (divider + 5) / 10;

        STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_R_DIV, rDivOpt);
        STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG1], TNG1_N_DIV_11_8, MSB(divider));
        STV6110x_SETFIELD(stv6110x->regs[STV6110x_TNG0], TNG0_N_DIV_7_0, LSB(divider));

        /* VCO Auto calibration */
        STV6110x_SETFIELD(stv6110x->regs[STV6110x_STAT1], STAT1_CALVCO_STRT, 1);

        stv6110x_write_reg(stv6110x, STV6110x_CTRL1, stv6110x->regs[STV6110x_CTRL1]);
        stv6110x_write_reg(stv6110x, STV6110x_TNG1, stv6110x->regs[STV6110x_TNG1]);
        stv6110x_write_reg(stv6110x, STV6110x_TNG0, stv6110x->regs[STV6110x_TNG0]);
        stv6110x_write_reg(stv6110x, STV6110x_STAT1, stv6110x->regs[STV6110x_STAT1]);

        for (i = 0; i < TRIALS; i++) {
                stv6110x_read_reg(stv6110x, STV6110x_STAT1, &stv6110x->regs[STV6110x_STAT1]);
                if (!STV6110x_GETFIELD(STAT1_CALVCO_STRT, stv6110x->regs[STV6110x_STAT1]))
                                break;
                msleep(1);
        }

        return 0;
}

static int stv6110x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        stv6110x_read_reg(stv6110x, STV6110x_TNG1, &stv6110x->regs[STV6110x_TNG1]);
        stv6110x_read_reg(stv6110x, STV6110x_TNG0, &stv6110x->regs[STV6110x_TNG0]);

        *frequency = (MAKEWORD16(STV6110x_GETFIELD(TNG1_N_DIV_11_8, stv6110x->regs[STV6110x_TNG1]),
                                 STV6110x_GETFIELD(TNG0_N_DIV_7_0, stv6110x->regs[STV6110x_TNG0]))) * REFCLOCK_kHz;

        *frequency /= (1 << (STV6110x_GETFIELD(TNG1_R_DIV, stv6110x->regs[STV6110x_TNG1]) +
                             STV6110x_GETFIELD(TNG1_DIV4SEL, stv6110x->regs[STV6110x_TNG1])));

        *frequency >>= 2;

        return 0;
}

static int stv6110x_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;
        u32 halfbw;
        u8 i;

        halfbw = bandwidth >> 1;

        if (halfbw > 36000000)
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL3], CTRL3_CF, 31); /* LPF */
        else if (halfbw < 5000000)
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL3], CTRL3_CF, 0); /* LPF */
        else
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL3], CTRL3_CF, ((halfbw / 1000000) - 5)); /* LPF */


        STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL3], CTRL3_RCCLK_OFF, 0x0); /* cal. clk activated */
        STV6110x_SETFIELD(stv6110x->regs[STV6110x_STAT1], STAT1_CALRC_STRT, 0x1); /* LPF auto cal */

        stv6110x_write_reg(stv6110x, STV6110x_CTRL3, stv6110x->regs[STV6110x_CTRL3]);
        stv6110x_write_reg(stv6110x, STV6110x_STAT1, stv6110x->regs[STV6110x_STAT1]);

        for (i = 0; i < TRIALS; i++) {
                stv6110x_read_reg(stv6110x, STV6110x_STAT1, &stv6110x->regs[STV6110x_STAT1]);
                if (!STV6110x_GETFIELD(STAT1_CALRC_STRT, stv6110x->regs[STV6110x_STAT1]))
                        break;
                msleep(1);
        }
        STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL3], CTRL3_RCCLK_OFF, 0x1); /* cal. done */
        stv6110x_write_reg(stv6110x, STV6110x_CTRL3, stv6110x->regs[STV6110x_CTRL3]);

        return 0;
}

static int stv6110x_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        stv6110x_read_reg(stv6110x, STV6110x_CTRL3, &stv6110x->regs[STV6110x_CTRL3]);
        *bandwidth = (STV6110x_GETFIELD(CTRL3_CF, stv6110x->regs[STV6110x_CTRL3]) + 5) * 2000000;

        return 0;
}

static int stv6110x_set_refclock(struct dvb_frontend *fe, u32 refclock)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        /* setup divider */
        switch (refclock) {
        default:
        case 1:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2], CTRL2_CO_DIV, 0);
                break;
        case 2:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2], CTRL2_CO_DIV, 1);
                break;
        case 4:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2], CTRL2_CO_DIV, 2);
                break;
        case 8:
        case 0:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2], CTRL2_CO_DIV, 3);
                break;
        }
        stv6110x_write_reg(stv6110x, STV6110x_CTRL2, stv6110x->regs[STV6110x_CTRL2]);

        return 0;
}

static int stv6110x_get_bbgain(struct dvb_frontend *fe, u32 *gain)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        stv6110x_read_reg(stv6110x, STV6110x_CTRL2, &stv6110x->regs[STV6110x_CTRL2]);
        *gain = 2 * STV6110x_GETFIELD(CTRL2_BBGAIN, stv6110x->regs[STV6110x_CTRL2]);

        return 0;
}

static int stv6110x_set_bbgain(struct dvb_frontend *fe, u32 gain)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2], CTRL2_BBGAIN, gain / 2);
        stv6110x_write_reg(stv6110x, STV6110x_CTRL2, stv6110x->regs[STV6110x_CTRL2]);

        return 0;
}

static int stv6110x_set_mode(struct dvb_frontend *fe, enum tuner_mode mode)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;
        int ret;

        switch (mode) {
        case TUNER_SLEEP:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_SYN, 0);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_RX, 0);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_LPT, 0);
                break;

        case TUNER_WAKE:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_SYN, 1);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_RX, 1);
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL1], CTRL1_LPT, 1);
                break;
        }

        ret = stv6110x_write_reg(stv6110x, STV6110x_CTRL1, stv6110x->regs[STV6110x_CTRL1]);
        if (ret < 0) {
                dprintk(FE_ERROR, 1, "I/O Error");
                return -EIO;
        }

        return 0;
}

static int stv6110x_sleep(struct dvb_frontend *fe)
{
        if (fe->tuner_priv)
                return stv6110x_set_mode(fe, TUNER_SLEEP);

        return 0;
}

static int stv6110x_get_status(struct dvb_frontend *fe, u32 *status)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        stv6110x_read_reg(stv6110x, STV6110x_STAT1, &stv6110x->regs[STV6110x_STAT1]);

        if (STV6110x_GETFIELD(STAT1_LOCK, stv6110x->regs[STV6110x_STAT1]))
                *status = TUNER_PHASELOCKED;
        else
                *status = 0;

        return 0;
}


static void stv6110x_release(struct dvb_frontend *fe)
{
        struct stv6110x_state *stv6110x = fe->tuner_priv;

        fe->tuner_priv = NULL;
        kfree(stv6110x);
}

static void st6110x_init_regs(struct stv6110x_state *stv6110x)
{
        u8 default_regs[] = {0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e};

        memcpy(stv6110x->regs, default_regs, 8);
}

static void stv6110x_setup_divider(struct stv6110x_state *stv6110x)
{
        switch (stv6110x->config->clk_div) {
        default:
        case 1:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2],
                                  CTRL2_CO_DIV,
                                  0);
                break;
        case 2:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2],
                                  CTRL2_CO_DIV,
                                  1);
                break;
        case 4:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2],
                                  CTRL2_CO_DIV,
                                  2);
                break;
        case 8:
        case 0:
                STV6110x_SETFIELD(stv6110x->regs[STV6110x_CTRL2],
                                  CTRL2_CO_DIV,
                                  3);
                break;
        }
}

static const struct dvb_tuner_ops stv6110x_ops = {
        .info = {
                .name             = "STV6110(A) Silicon Tuner",
                .frequency_min_hz =  950 * MHz,
                .frequency_max_hz = 2150 * MHz,
        },
        .release                = stv6110x_release
};

static struct stv6110x_devctl stv6110x_ctl = {
        .tuner_init             = stv6110x_init,
        .tuner_sleep            = stv6110x_sleep,
        .tuner_set_mode         = stv6110x_set_mode,
        .tuner_set_frequency    = stv6110x_set_frequency,
        .tuner_get_frequency    = stv6110x_get_frequency,
        .tuner_set_bandwidth    = stv6110x_set_bandwidth,
        .tuner_get_bandwidth    = stv6110x_get_bandwidth,
        .tuner_set_bbgain       = stv6110x_set_bbgain,
        .tuner_get_bbgain       = stv6110x_get_bbgain,
        .tuner_set_refclk       = stv6110x_set_refclock,
        .tuner_get_status       = stv6110x_get_status,
};

static void stv6110x_set_frontend_opts(struct stv6110x_state *stv6110x)
{
        stv6110x->frontend->tuner_priv          = stv6110x;
        stv6110x->frontend->ops.tuner_ops       = stv6110x_ops;
}

static struct stv6110x_devctl *stv6110x_get_devctl(struct i2c_client *client)
{
        struct stv6110x_state *stv6110x = i2c_get_clientdata(client);

        dev_dbg(&client->dev, "\n");

        return stv6110x->devctl;
}

static int stv6110x_probe(struct i2c_client *client)
{
        struct stv6110x_config *config = client->dev.platform_data;

        struct stv6110x_state *stv6110x;

        stv6110x = kzalloc_obj(*stv6110x);
        if (!stv6110x)
                return -ENOMEM;

        stv6110x->frontend      = config->frontend;
        stv6110x->i2c           = client->adapter;
        stv6110x->config        = config;
        stv6110x->devctl        = &stv6110x_ctl;

        st6110x_init_regs(stv6110x);
        stv6110x_setup_divider(stv6110x);
        stv6110x_set_frontend_opts(stv6110x);

        dev_info(&stv6110x->i2c->dev, "Probed STV6110x\n");

        i2c_set_clientdata(client, stv6110x);

        /* setup callbacks */
        config->get_devctl = stv6110x_get_devctl;

        return 0;
}

static void stv6110x_remove(struct i2c_client *client)
{
        struct stv6110x_state *stv6110x = i2c_get_clientdata(client);

        stv6110x_release(stv6110x->frontend);
}

const struct stv6110x_devctl *stv6110x_attach(struct dvb_frontend *fe,
                                        const struct stv6110x_config *config,
                                        struct i2c_adapter *i2c)
{
        struct stv6110x_state *stv6110x;

        stv6110x = kzalloc_obj(*stv6110x);
        if (!stv6110x)
                return NULL;

        stv6110x->frontend      = fe;
        stv6110x->i2c           = i2c;
        stv6110x->config        = config;
        stv6110x->devctl        = &stv6110x_ctl;

        st6110x_init_regs(stv6110x);
        stv6110x_setup_divider(stv6110x);
        stv6110x_set_frontend_opts(stv6110x);

        fe->tuner_priv          = stv6110x;
        fe->ops.tuner_ops       = stv6110x_ops;

        dev_info(&stv6110x->i2c->dev, "Attaching STV6110x\n");
        return stv6110x->devctl;
}
EXPORT_SYMBOL_GPL(stv6110x_attach);

static const struct i2c_device_id stv6110x_id_table[] = {
        { "stv6110x" },
        {}
};
MODULE_DEVICE_TABLE(i2c, stv6110x_id_table);

static struct i2c_driver stv6110x_driver = {
        .driver = {
                .name   = "stv6110x",
                .suppress_bind_attrs = true,
        },
        .probe          = stv6110x_probe,
        .remove         = stv6110x_remove,
        .id_table       = stv6110x_id_table,
};

module_i2c_driver(stv6110x_driver);

MODULE_AUTHOR("Manu Abraham");
MODULE_DESCRIPTION("STV6110x Silicon tuner");
MODULE_LICENSE("GPL");