// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * ZyDAS ZD1301 driver (demodulator)
 *
 * Copyright (C) 2015 Antti Palosaari <crope@iki.fi>
 */

#include "zd1301_demod.h"

static u8 zd1301_demod_gain = 0x38;
module_param_named(gain, zd1301_demod_gain, byte, 0644);
MODULE_PARM_DESC(gain, "gain (value: 0x00 - 0x70, default: 0x38)");

struct zd1301_demod_dev {
        struct platform_device *pdev;
        struct dvb_frontend frontend;
        struct i2c_adapter adapter;
        u8 gain;
};

static int zd1301_demod_wreg(struct zd1301_demod_dev *dev, u16 reg, u8 val)
{
        struct platform_device *pdev = dev->pdev;
        struct zd1301_demod_platform_data *pdata = pdev->dev.platform_data;

        return pdata->reg_write(pdata->reg_priv, reg, val);
}

static int zd1301_demod_rreg(struct zd1301_demod_dev *dev, u16 reg, u8 *val)
{
        struct platform_device *pdev = dev->pdev;
        struct zd1301_demod_platform_data *pdata = pdev->dev.platform_data;

        return pdata->reg_read(pdata->reg_priv, reg, val);
}

static int zd1301_demod_set_frontend(struct dvb_frontend *fe)
{
        struct zd1301_demod_dev *dev = fe->demodulator_priv;
        struct platform_device *pdev = dev->pdev;
        struct dtv_frontend_properties *c = &fe->dtv_property_cache;
        int ret;
        u32 if_frequency;
        u8 r6a50_val;

        dev_dbg(&pdev->dev, "frequency=%u bandwidth_hz=%u\n",
                c->frequency, c->bandwidth_hz);

        /* Program tuner */
        if (fe->ops.tuner_ops.set_params &&
            fe->ops.tuner_ops.get_if_frequency) {
                ret = fe->ops.tuner_ops.set_params(fe);
                if (ret)
                        goto err;
                ret = fe->ops.tuner_ops.get_if_frequency(fe, &if_frequency);
                if (ret)
                        goto err;
        } else {
                ret = -EINVAL;
                goto err;
        }

        dev_dbg(&pdev->dev, "if_frequency=%u\n", if_frequency);
        if (if_frequency != 36150000) {
                ret = -EINVAL;
                goto err;
        }

        switch (c->bandwidth_hz) {
        case 6000000:
                r6a50_val = 0x78;
                break;
        case 7000000:
                r6a50_val = 0x68;
                break;
        case 8000000:
                r6a50_val = 0x58;
                break;
        default:
                ret = -EINVAL;
                goto err;
        }

        ret = zd1301_demod_wreg(dev, 0x6a60, 0x11);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a47, 0x46);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a48, 0x46);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a4a, 0x15);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a4b, 0x63);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a5b, 0x99);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a3b, 0x10);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6806, 0x01);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a41, 0x08);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a42, 0x46);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a44, 0x14);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a45, 0x67);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a38, 0x00);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a4c, 0x52);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a49, 0x2a);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6840, 0x2e);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a50, r6a50_val);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a38, 0x07);
        if (ret)
                goto err;

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

static int zd1301_demod_sleep(struct dvb_frontend *fe)
{
        struct zd1301_demod_dev *dev = fe->demodulator_priv;
        struct platform_device *pdev = dev->pdev;
        int ret;

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

        ret = zd1301_demod_wreg(dev, 0x6a43, 0x70);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x684e, 0x00);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6849, 0x00);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x68e2, 0xd7);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x68e0, 0x39);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6840, 0x21);
        if (ret)
                goto err;

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

static int zd1301_demod_init(struct dvb_frontend *fe)
{
        struct zd1301_demod_dev *dev = fe->demodulator_priv;
        struct platform_device *pdev = dev->pdev;
        int ret;

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

        ret = zd1301_demod_wreg(dev, 0x6840, 0x26);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x68e0, 0xff);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x68e2, 0xd8);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6849, 0x4e);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x684e, 0x01);
        if (ret)
                goto err;
        ret = zd1301_demod_wreg(dev, 0x6a43, zd1301_demod_gain);
        if (ret)
                goto err;

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

static int zd1301_demod_get_tune_settings(struct dvb_frontend *fe,
                                          struct dvb_frontend_tune_settings *settings)
{
        struct zd1301_demod_dev *dev = fe->demodulator_priv;
        struct platform_device *pdev = dev->pdev;

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

        /* ~180ms seems to be enough */
        settings->min_delay_ms = 400;

        return 0;
}

static int zd1301_demod_read_status(struct dvb_frontend *fe,
                                    enum fe_status *status)
{
        struct zd1301_demod_dev *dev = fe->demodulator_priv;
        struct platform_device *pdev = dev->pdev;
        int ret;
        u8 u8tmp;

        ret = zd1301_demod_rreg(dev, 0x6a24, &u8tmp);
        if (ret)
                goto err;
        if (u8tmp > 0x00 && u8tmp < 0x20)
                *status = FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI |
                          FE_HAS_SYNC | FE_HAS_LOCK;
        else
                *status = 0;

        dev_dbg(&pdev->dev, "lock byte=%02x\n", u8tmp);

        /*
         * Interesting registers here are:
         * 0x6a05: get some gain value
         * 0x6a06: get about same gain value than set to 0x6a43
         * 0x6a07: get some gain value
         * 0x6a43: set gain value by driver
         * 0x6a24: get demod lock bits (FSM stage?)
         *
         * Driver should implement some kind of algorithm to calculate suitable
         * value for register 0x6a43, based likely values from register 0x6a05
         * and 0x6a07. Looks like gain register 0x6a43 value could be from
         * range 0x00 - 0x70.
         */

        if (dev->gain != zd1301_demod_gain) {
                dev->gain = zd1301_demod_gain;

                ret = zd1301_demod_wreg(dev, 0x6a43, dev->gain);
                if (ret)
                        goto err;
        }

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

static const struct dvb_frontend_ops zd1301_demod_ops = {
        .delsys = {SYS_DVBT},
        .info = {
                .name = "ZyDAS ZD1301",
                .caps = FE_CAN_FEC_1_2 |
                        FE_CAN_FEC_2_3 |
                        FE_CAN_FEC_3_4 |
                        FE_CAN_FEC_5_6 |
                        FE_CAN_FEC_7_8 |
                        FE_CAN_FEC_AUTO |
                        FE_CAN_QPSK |
                        FE_CAN_QAM_16 |
                        FE_CAN_QAM_64 |
                        FE_CAN_QAM_AUTO |
                        FE_CAN_TRANSMISSION_MODE_AUTO |
                        FE_CAN_GUARD_INTERVAL_AUTO |
                        FE_CAN_HIERARCHY_AUTO |
                        FE_CAN_MUTE_TS
        },

        .sleep = zd1301_demod_sleep,
        .init = zd1301_demod_init,
        .set_frontend = zd1301_demod_set_frontend,
        .get_tune_settings = zd1301_demod_get_tune_settings,
        .read_status = zd1301_demod_read_status,
};

struct dvb_frontend *zd1301_demod_get_dvb_frontend(struct platform_device *pdev)
{
        struct zd1301_demod_dev *dev = platform_get_drvdata(pdev);

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

        return &dev->frontend;
}
EXPORT_SYMBOL(zd1301_demod_get_dvb_frontend);

static int zd1301_demod_i2c_master_xfer(struct i2c_adapter *adapter,
                                        struct i2c_msg msg[], int num)
{
        struct zd1301_demod_dev *dev = i2c_get_adapdata(adapter);
        struct platform_device *pdev = dev->pdev;
        int ret, i;
        unsigned long timeout;
        u8 u8tmp;

        #define I2C_XFER_TIMEOUT 5
        #define ZD1301_IS_I2C_XFER_WRITE_READ(_msg, _num) \
                (_num == 2 && !(_msg[0].flags & I2C_M_RD) && (_msg[1].flags & I2C_M_RD))
        #define ZD1301_IS_I2C_XFER_WRITE(_msg, _num) \
                (_num == 1 && !(_msg[0].flags & I2C_M_RD))
        #define ZD1301_IS_I2C_XFER_READ(_msg, _num) \
                (_num == 1 && (_msg[0].flags & I2C_M_RD))
        if (ZD1301_IS_I2C_XFER_WRITE_READ(msg, num)) {
                dev_dbg(&pdev->dev, "write&read msg[0].len=%u msg[1].len=%u\n",
                        msg[0].len, msg[1].len);
                if (msg[0].len > 1 || msg[1].len > 8) {
                        ret = -EOPNOTSUPP;
                        goto err;
                }

                ret = zd1301_demod_wreg(dev, 0x6811, 0x80);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6812, 0x05);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6813, msg[1].addr << 1);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6801, msg[0].buf[0]);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6802, 0x00);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6803, 0x06);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6805, 0x00);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6804, msg[1].len);
                if (ret)
                        goto err;

                /* Poll xfer ready */
                timeout = jiffies + msecs_to_jiffies(I2C_XFER_TIMEOUT);
                for (u8tmp = 1; !time_after(jiffies, timeout) && u8tmp;) {
                        usleep_range(500, 800);

                        ret = zd1301_demod_rreg(dev, 0x6804, &u8tmp);
                        if (ret)
                                goto err;
                }

                for (i = 0; i < msg[1].len; i++) {
                        ret = zd1301_demod_rreg(dev, 0x0600 + i, &msg[1].buf[i]);
                        if (ret)
                                goto err;
                }
        } else if (ZD1301_IS_I2C_XFER_WRITE(msg, num)) {
                dev_dbg(&pdev->dev, "write msg[0].len=%u\n", msg[0].len);
                if (msg[0].len > 1 + 8) {
                        ret = -EOPNOTSUPP;
                        goto err;
                }

                ret = zd1301_demod_wreg(dev, 0x6811, 0x80);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6812, 0x01);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6813, msg[0].addr << 1);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6800, msg[0].buf[0]);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6802, 0x00);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6803, 0x06);
                if (ret)
                        goto err;

                for (i = 0; i < msg[0].len - 1; i++) {
                        ret = zd1301_demod_wreg(dev, 0x0600 + i, msg[0].buf[1 + i]);
                        if (ret)
                                goto err;
                }

                ret = zd1301_demod_wreg(dev, 0x6805, 0x80);
                if (ret)
                        goto err;
                ret = zd1301_demod_wreg(dev, 0x6804, msg[0].len - 1);
                if (ret)
                        goto err;

                /* Poll xfer ready */
                timeout = jiffies + msecs_to_jiffies(I2C_XFER_TIMEOUT);
                for (u8tmp = 1; !time_after(jiffies, timeout) && u8tmp;) {
                        usleep_range(500, 800);

                        ret = zd1301_demod_rreg(dev, 0x6804, &u8tmp);
                        if (ret)
                                goto err;
                }
        } else {
                dev_dbg(&pdev->dev, "unknown msg[0].len=%u\n", msg[0].len);
                ret = -EOPNOTSUPP;
                goto err;
        }

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

static u32 zd1301_demod_i2c_functionality(struct i2c_adapter *adapter)
{
        return I2C_FUNC_I2C;
}

static const struct i2c_algorithm zd1301_demod_i2c_algorithm = {
        .master_xfer   = zd1301_demod_i2c_master_xfer,
        .functionality = zd1301_demod_i2c_functionality,
};

struct i2c_adapter *zd1301_demod_get_i2c_adapter(struct platform_device *pdev)
{
        struct zd1301_demod_dev *dev = platform_get_drvdata(pdev);

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

        return &dev->adapter;
}
EXPORT_SYMBOL(zd1301_demod_get_i2c_adapter);

/* Platform driver interface */
static int zd1301_demod_probe(struct platform_device *pdev)
{
        struct zd1301_demod_dev *dev;
        struct zd1301_demod_platform_data *pdata = pdev->dev.platform_data;
        int ret;

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

        if (!pdata) {
                ret = -EINVAL;
                dev_err(&pdev->dev, "cannot proceed without platform data\n");
                goto err;
        }
        if (!pdev->dev.parent->driver) {
                ret = -EINVAL;
                dev_dbg(&pdev->dev, "no parent device\n");
                goto err;
        }

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

        /* Setup the state */
        dev->pdev = pdev;
        dev->gain = zd1301_demod_gain;

        /* Sleep */
        ret = zd1301_demod_wreg(dev, 0x6840, 0x21);
        if (ret)
                goto err_kfree;
        ret = zd1301_demod_wreg(dev, 0x6a38, 0x07);
        if (ret)
                goto err_kfree;

        /* Create I2C adapter */
        strscpy(dev->adapter.name, "ZyDAS ZD1301 demod",
                sizeof(dev->adapter.name));
        dev->adapter.algo = &zd1301_demod_i2c_algorithm;
        dev->adapter.algo_data = NULL;
        dev->adapter.dev.parent = pdev->dev.parent;
        i2c_set_adapdata(&dev->adapter, dev);
        ret = i2c_add_adapter(&dev->adapter);
        if (ret) {
                dev_err(&pdev->dev, "I2C adapter add failed %d\n", ret);
                goto err_kfree;
        }

        /* Create dvb frontend */
        memcpy(&dev->frontend.ops, &zd1301_demod_ops, sizeof(dev->frontend.ops));
        dev->frontend.demodulator_priv = dev;
        platform_set_drvdata(pdev, dev);
        dev_info(&pdev->dev, "ZyDAS ZD1301 demod attached\n");

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

static void zd1301_demod_remove(struct platform_device *pdev)
{
        struct zd1301_demod_dev *dev = platform_get_drvdata(pdev);

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

        i2c_del_adapter(&dev->adapter);
        kfree(dev);
}

static struct platform_driver zd1301_demod_driver = {
        .driver = {
                .name                = "zd1301_demod",
                .suppress_bind_attrs = true,
        },
        .probe          = zd1301_demod_probe,
        .remove         = zd1301_demod_remove,
};
module_platform_driver(zd1301_demod_driver);

MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
MODULE_DESCRIPTION("ZyDAS ZD1301 demodulator driver");
MODULE_LICENSE("GPL");