// SPDX-License-Identifier: GPL-2.0-or-later
/*
    Driver for ST STV0299 demodulator

    Copyright (C) 2001-2002 Convergence Integrated Media GmbH
        <ralph@convergence.de>,
        <holger@convergence.de>,
        <js@convergence.de>


    Philips SU1278/SH

    Copyright (C) 2002 by Peter Schildmann <peter.schildmann@web.de>


    LG TDQF-S001F

    Copyright (C) 2002 Felix Domke <tmbinc@elitedvb.net>
                     & Andreas Oberritter <obi@linuxtv.org>


    Support for Samsung TBMU24112IMB used on Technisat SkyStar2 rev. 2.6B

    Copyright (C) 2003 Vadim Catana <skystar@moldova.cc>:

    Support for Philips SU1278 on Technotrend hardware

    Copyright (C) 2004 Andrew de Quincey <adq_dvb@lidskialf.net>


*/

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <asm/div64.h>

#include <media/dvb_frontend.h>
#include "stv0299.h"

struct stv0299_state {
        struct i2c_adapter* i2c;
        const struct stv0299_config* config;
        struct dvb_frontend frontend;

        u8 initialised:1;
        u32 tuner_frequency;
        u32 symbol_rate;
        enum fe_code_rate fec_inner;
        int errmode;
        u32 ucblocks;
        u8 mcr_reg;
};

#define STATUS_BER 0
#define STATUS_UCBLOCKS 1

static int debug;
static int debug_legacy_dish_switch;
#define dprintk(args...) \
        do { \
                if (debug) printk(KERN_DEBUG "stv0299: " args); \
        } while (0)


static int stv0299_writeregI (struct stv0299_state* state, u8 reg, u8 data)
{
        int ret;
        u8 buf [] = { reg, data };
        struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };

        ret = i2c_transfer (state->i2c, &msg, 1);

        if (ret != 1)
                dprintk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
                        __func__, reg, data, ret);

        return (ret != 1) ? -EREMOTEIO : 0;
}

static int stv0299_write(struct dvb_frontend* fe, const u8 buf[], int len)
{
        struct stv0299_state* state = fe->demodulator_priv;

        if (len != 2)
                return -EINVAL;

        return stv0299_writeregI(state, buf[0], buf[1]);
}

static u8 stv0299_readreg (struct stv0299_state* state, u8 reg)
{
        int ret;
        u8 b0 [] = { reg };
        u8 b1 [] = { 0 };
        struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
                           { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };

        ret = i2c_transfer (state->i2c, msg, 2);

        if (ret != 2)
                dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n",
                                __func__, reg, ret);

        return b1[0];
}

static int stv0299_readregs (struct stv0299_state* state, u8 reg1, u8 *b, u8 len)
{
        int ret;
        struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = &reg1, .len = 1 },
                           { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b, .len = len } };

        ret = i2c_transfer (state->i2c, msg, 2);

        if (ret != 2)
                dprintk("%s: readreg error (ret == %i)\n", __func__, ret);

        return ret == 2 ? 0 : ret;
}

static int stv0299_set_FEC(struct stv0299_state *state, enum fe_code_rate fec)
{
        dprintk ("%s\n", __func__);

        switch (fec) {
        case FEC_AUTO:
        {
                return stv0299_writeregI (state, 0x31, 0x1f);
        }
        case FEC_1_2:
        {
                return stv0299_writeregI (state, 0x31, 0x01);
        }
        case FEC_2_3:
        {
                return stv0299_writeregI (state, 0x31, 0x02);
        }
        case FEC_3_4:
        {
                return stv0299_writeregI (state, 0x31, 0x04);
        }
        case FEC_5_6:
        {
                return stv0299_writeregI (state, 0x31, 0x08);
        }
        case FEC_7_8:
        {
                return stv0299_writeregI (state, 0x31, 0x10);
        }
        default:
        {
                return -EINVAL;
        }
    }
}

static enum fe_code_rate stv0299_get_fec(struct stv0299_state *state)
{
        static const enum fe_code_rate fec_tab[] = {
                FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8, FEC_1_2
        };
        u8 index;

        dprintk ("%s\n", __func__);

        index = stv0299_readreg (state, 0x1b);
        index &= 0x7;

        if (index > 4)
                return FEC_AUTO;

        return fec_tab [index];
}

static int stv0299_wait_diseqc_fifo (struct stv0299_state* state, int timeout)
{
        unsigned long start = jiffies;

        dprintk ("%s\n", __func__);

        while (stv0299_readreg(state, 0x0a) & 1) {
                if (time_is_before_jiffies(start + timeout)) {
                        dprintk ("%s: timeout!!\n", __func__);
                        return -ETIMEDOUT;
                }
                msleep(10);
        }

        return 0;
}

static int stv0299_wait_diseqc_idle (struct stv0299_state* state, int timeout)
{
        unsigned long start = jiffies;

        dprintk ("%s\n", __func__);

        while ((stv0299_readreg(state, 0x0a) & 3) != 2 ) {
                if (time_is_before_jiffies(start + timeout)) {
                        dprintk ("%s: timeout!!\n", __func__);
                        return -ETIMEDOUT;
                }
                msleep(10);
        }

        return 0;
}

static int stv0299_set_symbolrate (struct dvb_frontend* fe, u32 srate)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u64 big = srate;
        u32 ratio;

        // check rate is within limits
        if ((srate < 1000000) || (srate > 45000000)) return -EINVAL;

        // calculate value to program
        big = big << 20;
        big += (state->config->mclk-1); // round correctly
        do_div(big, state->config->mclk);
        ratio = big << 4;

        return state->config->set_symbol_rate(fe, srate, ratio);
}

static int stv0299_get_symbolrate (struct stv0299_state* state)
{
        u32 Mclk = state->config->mclk / 4096L;
        u32 srate;
        s32 offset;
        u8 sfr[3];
        s8 rtf;

        dprintk ("%s\n", __func__);

        stv0299_readregs (state, 0x1f, sfr, 3);
        stv0299_readregs (state, 0x1a, (u8 *)&rtf, 1);

        srate = (sfr[0] << 8) | sfr[1];
        srate *= Mclk;
        srate /= 16;
        srate += (sfr[2] >> 4) * Mclk / 256;
        offset = (s32) rtf * (srate / 4096L);
        offset /= 128;

        dprintk ("%s : srate = %i\n", __func__, srate);
        dprintk ("%s : offset = %i\n", __func__, offset);

        srate += offset;

        srate += 1000;
        srate /= 2000;
        srate *= 2000;

        return srate;
}

static int stv0299_send_diseqc_msg (struct dvb_frontend* fe,
                                    struct dvb_diseqc_master_cmd *m)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u8 val;
        int i;

        dprintk ("%s\n", __func__);

        if (stv0299_wait_diseqc_idle (state, 100) < 0)
                return -ETIMEDOUT;

        val = stv0299_readreg (state, 0x08);

        if (stv0299_writeregI (state, 0x08, (val & ~0x7) | 0x6))  /* DiSEqC mode */
                return -EREMOTEIO;

        for (i=0; i<m->msg_len; i++) {
                if (stv0299_wait_diseqc_fifo (state, 100) < 0)
                        return -ETIMEDOUT;

                if (stv0299_writeregI (state, 0x09, m->msg[i]))
                        return -EREMOTEIO;
        }

        if (stv0299_wait_diseqc_idle (state, 100) < 0)
                return -ETIMEDOUT;

        return 0;
}

static int stv0299_send_diseqc_burst(struct dvb_frontend *fe,
                                     enum fe_sec_mini_cmd burst)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u8 val;

        dprintk ("%s\n", __func__);

        if (stv0299_wait_diseqc_idle (state, 100) < 0)
                return -ETIMEDOUT;

        val = stv0299_readreg (state, 0x08);

        if (stv0299_writeregI (state, 0x08, (val & ~0x7) | 0x2))        /* burst mode */
                return -EREMOTEIO;

        if (stv0299_writeregI (state, 0x09, burst == SEC_MINI_A ? 0x00 : 0xff))
                return -EREMOTEIO;

        if (stv0299_wait_diseqc_idle (state, 100) < 0)
                return -ETIMEDOUT;

        if (stv0299_writeregI (state, 0x08, val))
                return -EREMOTEIO;

        return 0;
}

static int stv0299_set_tone(struct dvb_frontend *fe,
                            enum fe_sec_tone_mode tone)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u8 val;

        if (stv0299_wait_diseqc_idle (state, 100) < 0)
                return -ETIMEDOUT;

        val = stv0299_readreg (state, 0x08);

        switch (tone) {
        case SEC_TONE_ON:
                return stv0299_writeregI (state, 0x08, val | 0x3);

        case SEC_TONE_OFF:
                return stv0299_writeregI (state, 0x08, (val & ~0x3) | 0x02);

        default:
                return -EINVAL;
        }
}

static int stv0299_set_voltage(struct dvb_frontend *fe,
                               enum fe_sec_voltage voltage)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u8 reg0x08;
        u8 reg0x0c;

        dprintk("%s: %s\n", __func__,
                voltage == SEC_VOLTAGE_13 ? "SEC_VOLTAGE_13" :
                voltage == SEC_VOLTAGE_18 ? "SEC_VOLTAGE_18" : "??");

        reg0x08 = stv0299_readreg (state, 0x08);
        reg0x0c = stv0299_readreg (state, 0x0c);

        /*
         *  H/V switching over OP0, OP1 and OP2 are LNB power enable bits
         */
        reg0x0c &= 0x0f;
        reg0x08 = (reg0x08 & 0x3f) | (state->config->lock_output << 6);

        switch (voltage) {
        case SEC_VOLTAGE_13:
                if (state->config->volt13_op0_op1 == STV0299_VOLT13_OP0)
                        reg0x0c |= 0x10; /* OP1 off, OP0 on */
                else
                        reg0x0c |= 0x40; /* OP1 on, OP0 off */
                break;
        case SEC_VOLTAGE_18:
                reg0x0c |= 0x50; /* OP1 on, OP0 on */
                break;
        case SEC_VOLTAGE_OFF:
                /* LNB power off! */
                reg0x08 = 0x00;
                reg0x0c = 0x00;
                break;
        default:
                return -EINVAL;
        }

        if (state->config->op0_off)
                reg0x0c &= ~0x10;

        stv0299_writeregI(state, 0x08, reg0x08);
        return stv0299_writeregI(state, 0x0c, reg0x0c);
}

static int stv0299_send_legacy_dish_cmd (struct dvb_frontend* fe, unsigned long cmd)
{
        struct stv0299_state* state = fe->demodulator_priv;
        u8 reg0x08;
        u8 reg0x0c;
        u8 lv_mask = 0x40;
        u8 last = 1;
        int i;
        ktime_t nexttime;
        ktime_t tv[10];

        reg0x08 = stv0299_readreg (state, 0x08);
        reg0x0c = stv0299_readreg (state, 0x0c);
        reg0x0c &= 0x0f;
        stv0299_writeregI (state, 0x08, (reg0x08 & 0x3f) | (state->config->lock_output << 6));
        if (state->config->volt13_op0_op1 == STV0299_VOLT13_OP0)
                lv_mask = 0x10;

        cmd = cmd << 1;
        if (debug_legacy_dish_switch)
                printk ("%s switch command: 0x%04lx\n",__func__, cmd);

        nexttime = ktime_get_boottime();
        if (debug_legacy_dish_switch)
                tv[0] = nexttime;
        stv0299_writeregI (state, 0x0c, reg0x0c | 0x50); /* set LNB to 18V */

        dvb_frontend_sleep_until(&nexttime, 32000);

        for (i=0; i<9; i++) {
                if (debug_legacy_dish_switch)
                        tv[i+1] = ktime_get_boottime();
                if((cmd & 0x01) != last) {
                        /* set voltage to (last ? 13V : 18V) */
                        stv0299_writeregI (state, 0x0c, reg0x0c | (last ? lv_mask : 0x50));
                        last = (last) ? 0 : 1;
                }

                cmd = cmd >> 1;

                if (i != 8)
                        dvb_frontend_sleep_until(&nexttime, 8000);
        }
        if (debug_legacy_dish_switch) {
                printk ("%s(%d): switch delay (should be 32k followed by all 8k\n",
                        __func__, fe->dvb->num);
                for (i = 1; i < 10; i++)
                        printk("%d: %d\n", i,
                               (int) ktime_us_delta(tv[i], tv[i-1]));
        }

        return 0;
}

static int stv0299_init (struct dvb_frontend* fe)
{
        struct stv0299_state* state = fe->demodulator_priv;
        int i;
        u8 reg;
        u8 val;

        dprintk("stv0299: init chip\n");

        stv0299_writeregI(state, 0x02, 0x30 | state->mcr_reg);
        msleep(50);

        for (i = 0; ; i += 2)  {
                reg = state->config->inittab[i];
                val = state->config->inittab[i+1];
                if (reg == 0xff && val == 0xff)
                        break;
                if (reg == 0x0c && state->config->op0_off)
                        val &= ~0x10;
                if (reg == 0x2)
                        state->mcr_reg = val & 0xf;
                stv0299_writeregI(state, reg, val);
        }

        return 0;
}

static int stv0299_read_status(struct dvb_frontend *fe,
                               enum fe_status *status)
{
        struct stv0299_state* state = fe->demodulator_priv;

        u8 signal = 0xff - stv0299_readreg (state, 0x18);
        u8 sync = stv0299_readreg (state, 0x1b);

        dprintk ("%s : FE_READ_STATUS : VSTATUS: 0x%02x\n", __func__, sync);
        *status = 0;

        if (signal > 10)
                *status |= FE_HAS_SIGNAL;

        if (sync & 0x80)
                *status |= FE_HAS_CARRIER;

        if (sync & 0x10)
                *status |= FE_HAS_VITERBI;

        if (sync & 0x08)
                *status |= FE_HAS_SYNC;

        if ((sync & 0x98) == 0x98)
                *status |= FE_HAS_LOCK;

        return 0;
}

static int stv0299_read_ber(struct dvb_frontend* fe, u32* ber)
{
        struct stv0299_state* state = fe->demodulator_priv;

        if (state->errmode != STATUS_BER)
                return -ENOSYS;

        *ber = stv0299_readreg(state, 0x1e) | (stv0299_readreg(state, 0x1d) << 8);

        return 0;
}

static int stv0299_read_signal_strength(struct dvb_frontend* fe, u16* strength)
{
        struct stv0299_state* state = fe->demodulator_priv;

        s32 signal =  0xffff - ((stv0299_readreg (state, 0x18) << 8)
                               | stv0299_readreg (state, 0x19));

        dprintk ("%s : FE_READ_SIGNAL_STRENGTH : AGC2I: 0x%02x%02x, signal=0x%04x\n", __func__,
                 stv0299_readreg (state, 0x18),
                 stv0299_readreg (state, 0x19), (int) signal);

        signal = signal * 5 / 4;
        *strength = (signal > 0xffff) ? 0xffff : (signal < 0) ? 0 : signal;

        return 0;
}

static int stv0299_read_snr(struct dvb_frontend* fe, u16* snr)
{
        struct stv0299_state* state = fe->demodulator_priv;

        s32 xsnr = 0xffff - ((stv0299_readreg (state, 0x24) << 8)
                           | stv0299_readreg (state, 0x25));
        xsnr = 3 * (xsnr - 0xa100);
        *snr = (xsnr > 0xffff) ? 0xffff : (xsnr < 0) ? 0 : xsnr;

        return 0;
}

static int stv0299_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
{
        struct stv0299_state* state = fe->demodulator_priv;

        if (state->errmode != STATUS_UCBLOCKS)
                return -ENOSYS;

        state->ucblocks += stv0299_readreg(state, 0x1e);
        state->ucblocks += (stv0299_readreg(state, 0x1d) << 8);
        *ucblocks = state->ucblocks;

        return 0;
}

static int stv0299_set_frontend(struct dvb_frontend *fe)
{
        struct dtv_frontend_properties *p = &fe->dtv_property_cache;
        struct stv0299_state* state = fe->demodulator_priv;
        int invval = 0;

        dprintk ("%s : FE_SET_FRONTEND\n", __func__);
        if (state->config->set_ts_params)
                state->config->set_ts_params(fe, 0);

        // set the inversion
        if (p->inversion == INVERSION_OFF) invval = 0;
        else if (p->inversion == INVERSION_ON) invval = 1;
        else {
                printk("stv0299 does not support auto-inversion\n");
                return -EINVAL;
        }
        if (state->config->invert) invval = (~invval) & 1;
        stv0299_writeregI(state, 0x0c, (stv0299_readreg(state, 0x0c) & 0xfe) | invval);

        if (fe->ops.tuner_ops.set_params) {
                fe->ops.tuner_ops.set_params(fe);
                if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
        }

        stv0299_set_FEC(state, p->fec_inner);
        stv0299_set_symbolrate(fe, p->symbol_rate);
        stv0299_writeregI(state, 0x22, 0x00);
        stv0299_writeregI(state, 0x23, 0x00);

        state->tuner_frequency = p->frequency;
        state->fec_inner = p->fec_inner;
        state->symbol_rate = p->symbol_rate;

        return 0;
}

static int stv0299_get_frontend(struct dvb_frontend *fe,
                                struct dtv_frontend_properties *p)
{
        struct stv0299_state* state = fe->demodulator_priv;
        s32 derot_freq;
        int invval;

        derot_freq = (s32)(s16) ((stv0299_readreg (state, 0x22) << 8)
                                | stv0299_readreg (state, 0x23));

        derot_freq *= (state->config->mclk >> 16);
        derot_freq += 500;
        derot_freq /= 1000;

        p->frequency += derot_freq;

        invval = stv0299_readreg (state, 0x0c) & 1;
        if (state->config->invert) invval = (~invval) & 1;
        p->inversion = invval ? INVERSION_ON : INVERSION_OFF;

        p->fec_inner = stv0299_get_fec(state);
        p->symbol_rate = stv0299_get_symbolrate(state);

        return 0;
}

static int stv0299_sleep(struct dvb_frontend* fe)
{
        struct stv0299_state* state = fe->demodulator_priv;

        stv0299_writeregI(state, 0x02, 0xb0 | state->mcr_reg);
        state->initialised = 0;

        return 0;
}

static int stv0299_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
{
        struct stv0299_state* state = fe->demodulator_priv;

        if (enable) {
                stv0299_writeregI(state, 0x05, 0xb5);
        } else {
                stv0299_writeregI(state, 0x05, 0x35);
        }
        udelay(1);
        return 0;
}

static int stv0299_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
{
        struct stv0299_state* state = fe->demodulator_priv;
        struct dtv_frontend_properties *p = &fe->dtv_property_cache;

        fesettings->min_delay_ms = state->config->min_delay_ms;
        if (p->symbol_rate < 10000000) {
                fesettings->step_size = p->symbol_rate / 32000;
                fesettings->max_drift = 5000;
        } else {
                fesettings->step_size = p->symbol_rate / 16000;
                fesettings->max_drift = p->symbol_rate / 2000;
        }
        return 0;
}

static void stv0299_release(struct dvb_frontend* fe)
{
        struct stv0299_state* state = fe->demodulator_priv;
        kfree(state);
}

static const struct dvb_frontend_ops stv0299_ops;

struct dvb_frontend* stv0299_attach(const struct stv0299_config* config,
                                    struct i2c_adapter* i2c)
{
        struct stv0299_state* state = NULL;
        int id;

        /* allocate memory for the internal state */
        state = kzalloc_obj(struct stv0299_state);
        if (state == NULL) goto error;

        /* setup the state */
        state->config = config;
        state->i2c = i2c;
        state->initialised = 0;
        state->tuner_frequency = 0;
        state->symbol_rate = 0;
        state->fec_inner = 0;
        state->errmode = STATUS_BER;

        /* check if the demod is there */
        stv0299_writeregI(state, 0x02, 0x30); /* standby off */
        msleep(200);
        id = stv0299_readreg(state, 0x00);

        /* register 0x00 contains 0xa1 for STV0299 and STV0299B */
        /* register 0x00 might contain 0x80 when returning from standby */
        if (id != 0xa1 && id != 0x80) goto error;

        /* create dvb_frontend */
        memcpy(&state->frontend.ops, &stv0299_ops, sizeof(struct dvb_frontend_ops));
        state->frontend.demodulator_priv = state;
        return &state->frontend;

error:
        kfree(state);
        return NULL;
}

static const struct dvb_frontend_ops stv0299_ops = {
        .delsys = { SYS_DVBS },
        .info = {
                .name                   = "ST STV0299 DVB-S",
                .frequency_min_hz       =  950 * MHz,
                .frequency_max_hz       = 2150 * MHz,
                .frequency_stepsize_hz  =  125 * kHz,
                .symbol_rate_min        = 1000000,
                .symbol_rate_max        = 45000000,
                .symbol_rate_tolerance  = 500,  /* ppm */
                .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_QPSK |
                      FE_CAN_FEC_AUTO
        },

        .release = stv0299_release,

        .init = stv0299_init,
        .sleep = stv0299_sleep,
        .write = stv0299_write,
        .i2c_gate_ctrl = stv0299_i2c_gate_ctrl,

        .set_frontend = stv0299_set_frontend,
        .get_frontend = stv0299_get_frontend,
        .get_tune_settings = stv0299_get_tune_settings,

        .read_status = stv0299_read_status,
        .read_ber = stv0299_read_ber,
        .read_signal_strength = stv0299_read_signal_strength,
        .read_snr = stv0299_read_snr,
        .read_ucblocks = stv0299_read_ucblocks,

        .diseqc_send_master_cmd = stv0299_send_diseqc_msg,
        .diseqc_send_burst = stv0299_send_diseqc_burst,
        .set_tone = stv0299_set_tone,
        .set_voltage = stv0299_set_voltage,
        .dishnetwork_send_legacy_command = stv0299_send_legacy_dish_cmd,
};

module_param(debug_legacy_dish_switch, int, 0444);
MODULE_PARM_DESC(debug_legacy_dish_switch, "Enable timing analysis for Dish Network legacy switches");

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

MODULE_DESCRIPTION("ST STV0299 DVB Demodulator driver");
MODULE_AUTHOR("Ralph Metzler, Holger Waechtler, Peter Schildmann, Felix Domke, Andreas Oberritter, Andrew de Quincey, Kenneth Aafly");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL_GPL(stv0299_attach);