// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Mirics MSi001 silicon tuner driver
 *
 * Copyright (C) 2013 Antti Palosaari <crope@iki.fi>
 * Copyright (C) 2014 Antti Palosaari <crope@iki.fi>
 */

#include <linux/module.h>
#include <linux/gcd.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>

static const struct v4l2_frequency_band bands[] = {
        {
                .type = V4L2_TUNER_RF,
                .index = 0,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =   49000000,
                .rangehigh  =  263000000,
        }, {
                .type = V4L2_TUNER_RF,
                .index = 1,
                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =  390000000,
                .rangehigh  =  960000000,
        },
};

struct msi001_dev {
        struct spi_device *spi;
        struct v4l2_subdev sd;

        /* Controls */
        struct v4l2_ctrl_handler hdl;
        struct v4l2_ctrl *bandwidth_auto;
        struct v4l2_ctrl *bandwidth;
        struct v4l2_ctrl *lna_gain;
        struct v4l2_ctrl *mixer_gain;
        struct v4l2_ctrl *if_gain;

        unsigned int f_tuner;
};

static inline struct msi001_dev *sd_to_msi001_dev(struct v4l2_subdev *sd)
{
        return container_of(sd, struct msi001_dev, sd);
}

static int msi001_wreg(struct msi001_dev *dev, u32 data)
{
        /* Register format: 4 bits addr + 20 bits value */
        return spi_write(dev->spi, &data, 3);
};

static int msi001_set_gain(struct msi001_dev *dev, int lna_gain, int mixer_gain,
                           int if_gain)
{
        struct spi_device *spi = dev->spi;
        int ret;
        u32 reg;

        dev_dbg(&spi->dev, "lna=%d mixer=%d if=%d\n",
                lna_gain, mixer_gain, if_gain);

        reg = 1 << 0;
        reg |= (59 - if_gain) << 4;
        reg |= 0 << 10;
        reg |= (1 - mixer_gain) << 12;
        reg |= (1 - lna_gain) << 13;
        reg |= 4 << 14;
        reg |= 0 << 17;
        ret = msi001_wreg(dev, reg);
        if (ret)
                goto err;

        return 0;
err:
        dev_dbg(&spi->dev, "failed %d\n", ret);
        return ret;
};

static int msi001_set_tuner(struct msi001_dev *dev)
{
        struct spi_device *spi = dev->spi;
        int ret, i;
        unsigned int uitmp, div_n, k, k_thresh, k_frac, div_lo, f_if1;
        u32 reg;
        u64 f_vco;
        u8 mode, filter_mode;

        static const struct {
                u32 rf;
                u8 mode;
                u8 div_lo;
        } band_lut[] = {
                { 50000000, 0xe1, 16}, /* AM_MODE2, antenna 2 */
                {108000000, 0x42, 32}, /* VHF_MODE */
                {330000000, 0x44, 16}, /* B3_MODE */
                {960000000, 0x48,  4}, /* B45_MODE */
                {      ~0U, 0x50,  2}, /* BL_MODE */
        };
        static const struct {
                u32 freq;
                u8 filter_mode;
        } if_freq_lut[] = {
                {      0, 0x03}, /* Zero IF */
                { 450000, 0x02}, /* 450 kHz IF */
                {1620000, 0x01}, /* 1.62 MHz IF */
                {2048000, 0x00}, /* 2.048 MHz IF */
        };
        static const struct {
                u32 freq;
                u8 val;
        } bandwidth_lut[] = {
                { 200000, 0x00}, /* 200 kHz */
                { 300000, 0x01}, /* 300 kHz */
                { 600000, 0x02}, /* 600 kHz */
                {1536000, 0x03}, /* 1.536 MHz */
                {5000000, 0x04}, /* 5 MHz */
                {6000000, 0x05}, /* 6 MHz */
                {7000000, 0x06}, /* 7 MHz */
                {8000000, 0x07}, /* 8 MHz */
        };

        unsigned int f_rf = dev->f_tuner;

        /*
         * bandwidth (Hz)
         * 200000, 300000, 600000, 1536000, 5000000, 6000000, 7000000, 8000000
         */
        unsigned int bandwidth;

        /*
         * intermediate frequency (Hz)
         * 0, 450000, 1620000, 2048000
         */
        unsigned int f_if = 0;
        #define F_REF 24000000
        #define DIV_PRE_N 4
        #define F_VCO_STEP div_lo

        dev_dbg(&spi->dev, "f_rf=%d f_if=%d\n", f_rf, f_if);

        for (i = 0; i < ARRAY_SIZE(band_lut); i++) {
                if (f_rf <= band_lut[i].rf) {
                        mode = band_lut[i].mode;
                        div_lo = band_lut[i].div_lo;
                        break;
                }
        }
        if (i == ARRAY_SIZE(band_lut)) {
                ret = -EINVAL;
                goto err;
        }

        /* AM_MODE is upconverted */
        if ((mode >> 0) & 0x1)
                f_if1 =  5 * F_REF;
        else
                f_if1 =  0;

        for (i = 0; i < ARRAY_SIZE(if_freq_lut); i++) {
                if (f_if == if_freq_lut[i].freq) {
                        filter_mode = if_freq_lut[i].filter_mode;
                        break;
                }
        }
        if (i == ARRAY_SIZE(if_freq_lut)) {
                ret = -EINVAL;
                goto err;
        }

        /* filters */
        bandwidth = dev->bandwidth->val;
        bandwidth = clamp(bandwidth, 200000U, 8000000U);

        for (i = 0; i < ARRAY_SIZE(bandwidth_lut); i++) {
                if (bandwidth <= bandwidth_lut[i].freq) {
                        bandwidth = bandwidth_lut[i].val;
                        break;
                }
        }
        if (i == ARRAY_SIZE(bandwidth_lut)) {
                ret = -EINVAL;
                goto err;
        }

        dev->bandwidth->val = bandwidth_lut[i].freq;

        dev_dbg(&spi->dev, "bandwidth selected=%d\n", bandwidth_lut[i].freq);

        /*
         * Fractional-N synthesizer
         *
         *           +---------------------------------------+
         *           v                                       |
         *  Fref   +----+     +-------+         +----+     +------+     +---+
         * ------> | PD | --> |  VCO  | ------> | /4 | --> | /N.F | <-- | K |
         *         +----+     +-------+         +----+     +------+     +---+
         *                      |
         *                      |
         *                      v
         *                    +-------+  Fout
         *                    | /Rout | ------>
         *                    +-------+
         */

        /* Calculate PLL integer and fractional control word. */
        f_vco = (u64) (f_rf + f_if + f_if1) * div_lo;
        div_n = div_u64_rem(f_vco, DIV_PRE_N * F_REF, &k);
        k_thresh = (DIV_PRE_N * F_REF) / F_VCO_STEP;
        k_frac = div_u64((u64) k * k_thresh, (DIV_PRE_N * F_REF));

        /* Find out greatest common divisor and divide to smaller. */
        uitmp = gcd(k_thresh, k_frac);
        k_thresh /= uitmp;
        k_frac /= uitmp;

        /* Force divide to reg max. Resolution will be reduced. */
        uitmp = DIV_ROUND_UP(k_thresh, 4095);
        k_thresh = DIV_ROUND_CLOSEST(k_thresh, uitmp);
        k_frac = DIV_ROUND_CLOSEST(k_frac, uitmp);

        /* Calculate real RF set. */
        uitmp = (unsigned int) F_REF * DIV_PRE_N * div_n;
        uitmp += (unsigned int) F_REF * DIV_PRE_N * k_frac / k_thresh;
        uitmp /= div_lo;

        dev_dbg(&spi->dev,
                "f_rf=%u:%u f_vco=%llu div_n=%u k_thresh=%u k_frac=%u div_lo=%u\n",
                f_rf, uitmp, f_vco, div_n, k_thresh, k_frac, div_lo);

        ret = msi001_wreg(dev, 0x00000e);
        if (ret)
                goto err;

        ret = msi001_wreg(dev, 0x000003);
        if (ret)
                goto err;

        reg = 0 << 0;
        reg |= mode << 4;
        reg |= filter_mode << 12;
        reg |= bandwidth << 14;
        reg |= 0x02 << 17;
        reg |= 0x00 << 20;
        ret = msi001_wreg(dev, reg);
        if (ret)
                goto err;

        reg = 5 << 0;
        reg |= k_thresh << 4;
        reg |= 1 << 19;
        reg |= 1 << 21;
        ret = msi001_wreg(dev, reg);
        if (ret)
                goto err;

        reg = 2 << 0;
        reg |= k_frac << 4;
        reg |= div_n << 16;
        ret = msi001_wreg(dev, reg);
        if (ret)
                goto err;

        ret = msi001_set_gain(dev, dev->lna_gain->cur.val,
                              dev->mixer_gain->cur.val, dev->if_gain->cur.val);
        if (ret)
                goto err;

        reg = 6 << 0;
        reg |= 63 << 4;
        reg |= 4095 << 10;
        ret = msi001_wreg(dev, reg);
        if (ret)
                goto err;

        return 0;
err:
        dev_dbg(&spi->dev, "failed %d\n", ret);
        return ret;
}

static int msi001_standby(struct v4l2_subdev *sd)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);

        return msi001_wreg(dev, 0x000000);
}

static int msi001_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *v)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);
        struct spi_device *spi = dev->spi;

        dev_dbg(&spi->dev, "index=%d\n", v->index);

        strscpy(v->name, "Mirics MSi001", sizeof(v->name));
        v->type = V4L2_TUNER_RF;
        v->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
        v->rangelow =    49000000;
        v->rangehigh =  960000000;

        return 0;
}

static int msi001_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *v)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);
        struct spi_device *spi = dev->spi;

        dev_dbg(&spi->dev, "index=%d\n", v->index);
        return 0;
}

static int msi001_g_frequency(struct v4l2_subdev *sd, struct v4l2_frequency *f)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);
        struct spi_device *spi = dev->spi;

        dev_dbg(&spi->dev, "tuner=%d\n", f->tuner);
        f->frequency = dev->f_tuner;
        return 0;
}

static int msi001_s_frequency(struct v4l2_subdev *sd,
                              const struct v4l2_frequency *f)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);
        struct spi_device *spi = dev->spi;
        unsigned int band;

        dev_dbg(&spi->dev, "tuner=%d type=%d frequency=%u\n",
                f->tuner, f->type, f->frequency);

        if (f->frequency < ((bands[0].rangehigh + bands[1].rangelow) / 2))
                band = 0;
        else
                band = 1;
        dev->f_tuner = clamp_t(unsigned int, f->frequency,
                               bands[band].rangelow, bands[band].rangehigh);

        return msi001_set_tuner(dev);
}

static int msi001_enum_freq_bands(struct v4l2_subdev *sd,
                                  struct v4l2_frequency_band *band)
{
        struct msi001_dev *dev = sd_to_msi001_dev(sd);
        struct spi_device *spi = dev->spi;

        dev_dbg(&spi->dev, "tuner=%d type=%d index=%d\n",
                band->tuner, band->type, band->index);

        if (band->index >= ARRAY_SIZE(bands))
                return -EINVAL;

        band->capability = bands[band->index].capability;
        band->rangelow = bands[band->index].rangelow;
        band->rangehigh = bands[band->index].rangehigh;

        return 0;
}

static const struct v4l2_subdev_tuner_ops msi001_tuner_ops = {
        .standby                  = msi001_standby,
        .g_tuner                  = msi001_g_tuner,
        .s_tuner                  = msi001_s_tuner,
        .g_frequency              = msi001_g_frequency,
        .s_frequency              = msi001_s_frequency,
        .enum_freq_bands          = msi001_enum_freq_bands,
};

static const struct v4l2_subdev_ops msi001_ops = {
        .tuner                    = &msi001_tuner_ops,
};

static int msi001_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct msi001_dev *dev = container_of(ctrl->handler, struct msi001_dev, hdl);
        struct spi_device *spi = dev->spi;

        int ret;

        dev_dbg(&spi->dev, "id=%d name=%s val=%d min=%lld max=%lld step=%lld\n",
                ctrl->id, ctrl->name, ctrl->val, ctrl->minimum, ctrl->maximum,
                ctrl->step);

        switch (ctrl->id) {
        case V4L2_CID_RF_TUNER_BANDWIDTH_AUTO:
        case V4L2_CID_RF_TUNER_BANDWIDTH:
                ret = msi001_set_tuner(dev);
                break;
        case  V4L2_CID_RF_TUNER_LNA_GAIN:
                ret = msi001_set_gain(dev, dev->lna_gain->val,
                                      dev->mixer_gain->cur.val,
                                      dev->if_gain->cur.val);
                break;
        case  V4L2_CID_RF_TUNER_MIXER_GAIN:
                ret = msi001_set_gain(dev, dev->lna_gain->cur.val,
                                      dev->mixer_gain->val,
                                      dev->if_gain->cur.val);
                break;
        case  V4L2_CID_RF_TUNER_IF_GAIN:
                ret = msi001_set_gain(dev, dev->lna_gain->cur.val,
                                      dev->mixer_gain->cur.val,
                                      dev->if_gain->val);
                break;
        default:
                dev_dbg(&spi->dev, "unknown control %d\n", ctrl->id);
                ret = -EINVAL;
        }

        return ret;
}

static const struct v4l2_ctrl_ops msi001_ctrl_ops = {
        .s_ctrl                   = msi001_s_ctrl,
};

static int msi001_probe(struct spi_device *spi)
{
        struct msi001_dev *dev;
        int ret;

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

        dev = kzalloc_obj(*dev);
        if (!dev) {
                ret = -ENOMEM;
                goto err;
        }

        dev->spi = spi;
        dev->f_tuner = bands[0].rangelow;
        v4l2_spi_subdev_init(&dev->sd, spi, &msi001_ops);

        /* Register controls */
        v4l2_ctrl_handler_init(&dev->hdl, 5);
        dev->bandwidth_auto = v4l2_ctrl_new_std(&dev->hdl, &msi001_ctrl_ops,
                        V4L2_CID_RF_TUNER_BANDWIDTH_AUTO, 0, 1, 1, 1);
        dev->bandwidth = v4l2_ctrl_new_std(&dev->hdl, &msi001_ctrl_ops,
                        V4L2_CID_RF_TUNER_BANDWIDTH, 200000, 8000000, 1, 200000);
        if (dev->hdl.error) {
                ret = dev->hdl.error;
                dev_err(&spi->dev, "Could not initialize controls\n");
                /* control init failed, free handler */
                goto err_ctrl_handler_free;
        }

        v4l2_ctrl_auto_cluster(2, &dev->bandwidth_auto, 0, false);
        dev->lna_gain = v4l2_ctrl_new_std(&dev->hdl, &msi001_ctrl_ops,
                        V4L2_CID_RF_TUNER_LNA_GAIN, 0, 1, 1, 1);
        dev->mixer_gain = v4l2_ctrl_new_std(&dev->hdl, &msi001_ctrl_ops,
                        V4L2_CID_RF_TUNER_MIXER_GAIN, 0, 1, 1, 1);
        dev->if_gain = v4l2_ctrl_new_std(&dev->hdl, &msi001_ctrl_ops,
                        V4L2_CID_RF_TUNER_IF_GAIN, 0, 59, 1, 0);
        if (dev->hdl.error) {
                ret = dev->hdl.error;
                dev_err(&spi->dev, "Could not initialize controls\n");
                /* control init failed, free handler */
                goto err_ctrl_handler_free;
        }

        dev->sd.ctrl_handler = &dev->hdl;
        return 0;
err_ctrl_handler_free:
        v4l2_ctrl_handler_free(&dev->hdl);
        kfree(dev);
err:
        return ret;
}

static void msi001_remove(struct spi_device *spi)
{
        struct v4l2_subdev *sd = spi_get_drvdata(spi);
        struct msi001_dev *dev = sd_to_msi001_dev(sd);

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

        /*
         * Registered by v4l2_spi_new_subdev() from master driver, but we must
         * unregister it from here. Weird.
         */
        v4l2_device_unregister_subdev(&dev->sd);
        v4l2_ctrl_handler_free(&dev->hdl);
        kfree(dev);
}

static const struct spi_device_id msi001_id_table[] = {
        {"msi001", 0},
        {}
};
MODULE_DEVICE_TABLE(spi, msi001_id_table);

static struct spi_driver msi001_driver = {
        .driver = {
                .name   = "msi001",
                .suppress_bind_attrs = true,
        },
        .probe          = msi001_probe,
        .remove         = msi001_remove,
        .id_table       = msi001_id_table,
};
module_spi_driver(msi001_driver);

MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
MODULE_DESCRIPTION("Mirics MSi001");
MODULE_LICENSE("GPL");