// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *    Support for Legend Silicon GB20600 (a.k.a DMB-TH) demodulator
 *    LGS8913, LGS8GL5, LGS8G75
 *    experimental support LGS8G42, LGS8G52
 *
 *    Copyright (C) 2007-2009 David T.L. Wong <davidtlwong@gmail.com>
 *    Copyright (C) 2008 Sirius International (Hong Kong) Limited
 *    Timothy Lee <timothy.lee@siriushk.com> (for initial work on LGS8GL5)
 */

#include <asm/div64.h>
#include <linux/firmware.h>

#include <media/dvb_frontend.h>

#include "lgs8gxx.h"
#include "lgs8gxx_priv.h"

#define dprintk(args...) \
        do { \
                if (debug) \
                        printk(KERN_DEBUG "lgs8gxx: " args); \
        } while (0)

static int debug;
static int fake_signal_str = 1;

#define LGS8GXX_FIRMWARE "lgs8g75.fw"

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

module_param(fake_signal_str, int, 0644);
MODULE_PARM_DESC(fake_signal_str, "fake signal strength for LGS8913."
"Signal strength calculation is slow.(default:on).");

/* LGS8GXX internal helper functions */

static int lgs8gxx_write_reg(struct lgs8gxx_state *priv, u8 reg, u8 data)
{
        int ret;
        u8 buf[] = { reg, data };
        struct i2c_msg msg = { .flags = 0, .buf = buf, .len = 2 };

        msg.addr = priv->config->demod_address;
        if (priv->config->prod != LGS8GXX_PROD_LGS8G75 && reg >= 0xC0)
                msg.addr += 0x02;

        if (debug >= 2)
                dprintk("%s: reg=0x%02X, data=0x%02X\n", __func__, reg, data);

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

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

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

static int lgs8gxx_read_reg(struct lgs8gxx_state *priv, u8 reg, u8 *p_data)
{
        int ret;
        u8 dev_addr;

        u8 b0[] = { reg };
        u8 b1[] = { 0 };
        struct i2c_msg msg[] = {
                { .flags = 0, .buf = b0, .len = 1 },
                { .flags = I2C_M_RD, .buf = b1, .len = 1 },
        };

        dev_addr = priv->config->demod_address;
        if (priv->config->prod != LGS8GXX_PROD_LGS8G75 && reg >= 0xC0)
                dev_addr += 0x02;
        msg[1].addr =  msg[0].addr = dev_addr;

        ret = i2c_transfer(priv->i2c, msg, 2);
        if (ret != 2) {
                dprintk("%s: error reg=0x%x, ret=%i\n", __func__, reg, ret);
                return -1;
        }

        *p_data = b1[0];
        if (debug >= 2)
                dprintk("%s: reg=0x%02X, data=0x%02X\n", __func__, reg, b1[0]);
        return 0;
}

static int lgs8gxx_soft_reset(struct lgs8gxx_state *priv)
{
        lgs8gxx_write_reg(priv, 0x02, 0x00);
        msleep(1);
        lgs8gxx_write_reg(priv, 0x02, 0x01);
        msleep(100);

        return 0;
}

static int wait_reg_mask(struct lgs8gxx_state *priv, u8 reg, u8 mask,
        u8 val, u8 delay, u8 tries)
{
        u8 t;
        int i;

        for (i = 0; i < tries; i++) {
                lgs8gxx_read_reg(priv, reg, &t);

                if ((t & mask) == val)
                        return 0;
                msleep(delay);
        }

        return 1;
}

static int lgs8gxx_set_ad_mode(struct lgs8gxx_state *priv)
{
        const struct lgs8gxx_config *config = priv->config;
        u8 if_conf;

        if_conf = 0x10; /* AGC output on, RF_AGC output off; */

        if_conf |=
                ((config->ext_adc) ? 0x80 : 0x00) |
                ((config->if_neg_center) ? 0x04 : 0x00) |
                ((config->if_freq == 0) ? 0x08 : 0x00) | /* Baseband */
                ((config->adc_signed) ? 0x02 : 0x00) |
                ((config->if_neg_edge) ? 0x01 : 0x00);

        if (config->ext_adc &&
                (config->prod == LGS8GXX_PROD_LGS8G52)) {
                lgs8gxx_write_reg(priv, 0xBA, 0x40);
        }

        lgs8gxx_write_reg(priv, 0x07, if_conf);

        return 0;
}

static int lgs8gxx_set_if_freq(struct lgs8gxx_state *priv, u32 freq /*in kHz*/)
{
        u64 val;
        u32 v32;
        u32 if_clk;

        if_clk = priv->config->if_clk_freq;

        val = freq;
        if (freq != 0) {
                val <<= 32;
                if (if_clk != 0)
                        do_div(val, if_clk);
                v32 = val & 0xFFFFFFFF;
                dprintk("Set IF Freq to %dkHz\n", freq);
        } else {
                v32 = 0;
                dprintk("Set IF Freq to baseband\n");
        }
        dprintk("AFC_INIT_FREQ = 0x%08X\n", v32);

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_write_reg(priv, 0x08, 0xFF & (v32));
                lgs8gxx_write_reg(priv, 0x09, 0xFF & (v32 >> 8));
                lgs8gxx_write_reg(priv, 0x0A, 0xFF & (v32 >> 16));
                lgs8gxx_write_reg(priv, 0x0B, 0xFF & (v32 >> 24));
        } else {
                lgs8gxx_write_reg(priv, 0x09, 0xFF & (v32));
                lgs8gxx_write_reg(priv, 0x0A, 0xFF & (v32 >> 8));
                lgs8gxx_write_reg(priv, 0x0B, 0xFF & (v32 >> 16));
                lgs8gxx_write_reg(priv, 0x0C, 0xFF & (v32 >> 24));
        }

        return 0;
}

static int lgs8gxx_get_afc_phase(struct lgs8gxx_state *priv)
{
        u64 val;
        u32 v32 = 0;
        u8 reg_addr, t;
        int i;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
                reg_addr = 0x23;
        else
                reg_addr = 0x48;

        for (i = 0; i < 4; i++) {
                lgs8gxx_read_reg(priv, reg_addr, &t);
                v32 <<= 8;
                v32 |= t;
                reg_addr--;
        }

        val = v32;
        val *= priv->config->if_clk_freq;
        val >>= 32;
        dprintk("AFC = %u kHz\n", (u32)val);
        return 0;
}

static int lgs8gxx_set_mode_auto(struct lgs8gxx_state *priv)
{
        u8 t;
        u8 prod = priv->config->prod;

        if (prod == LGS8GXX_PROD_LGS8913)
                lgs8gxx_write_reg(priv, 0xC6, 0x01);

        if (prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_read_reg(priv, 0x0C, &t);
                t &= (~0x04);
                lgs8gxx_write_reg(priv, 0x0C, t | 0x80);
                lgs8gxx_write_reg(priv, 0x39, 0x00);
                lgs8gxx_write_reg(priv, 0x3D, 0x04);
        } else if (prod == LGS8GXX_PROD_LGS8913 ||
                prod == LGS8GXX_PROD_LGS8GL5 ||
                prod == LGS8GXX_PROD_LGS8G42 ||
                prod == LGS8GXX_PROD_LGS8G52 ||
                prod == LGS8GXX_PROD_LGS8G54) {
                lgs8gxx_read_reg(priv, 0x7E, &t);
                lgs8gxx_write_reg(priv, 0x7E, t | 0x01);

                /* clear FEC self reset */
                lgs8gxx_read_reg(priv, 0xC5, &t);
                lgs8gxx_write_reg(priv, 0xC5, t & 0xE0);
        }

        if (prod == LGS8GXX_PROD_LGS8913) {
                /* FEC auto detect */
                lgs8gxx_write_reg(priv, 0xC1, 0x03);

                lgs8gxx_read_reg(priv, 0x7C, &t);
                t = (t & 0x8C) | 0x03;
                lgs8gxx_write_reg(priv, 0x7C, t);

                /* BER test mode */
                lgs8gxx_read_reg(priv, 0xC3, &t);
                t = (t & 0xEF) |  0x10;
                lgs8gxx_write_reg(priv, 0xC3, t);
        }

        if (priv->config->prod == LGS8GXX_PROD_LGS8G52)
                lgs8gxx_write_reg(priv, 0xD9, 0x40);

        return 0;
}

static int lgs8gxx_set_mode_manual(struct lgs8gxx_state *priv)
{
        u8 t;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                u8 t2;
                lgs8gxx_read_reg(priv, 0x0C, &t);
                t &= (~0x80);
                lgs8gxx_write_reg(priv, 0x0C, t);

                lgs8gxx_read_reg(priv, 0x0C, &t);
                lgs8gxx_read_reg(priv, 0x19, &t2);

                if (((t&0x03) == 0x01) && (t2&0x01)) {
                        lgs8gxx_write_reg(priv, 0x6E, 0x05);
                        lgs8gxx_write_reg(priv, 0x39, 0x02);
                        lgs8gxx_write_reg(priv, 0x39, 0x03);
                        lgs8gxx_write_reg(priv, 0x3D, 0x05);
                        lgs8gxx_write_reg(priv, 0x3E, 0x28);
                        lgs8gxx_write_reg(priv, 0x53, 0x80);
                } else {
                        lgs8gxx_write_reg(priv, 0x6E, 0x3F);
                        lgs8gxx_write_reg(priv, 0x39, 0x00);
                        lgs8gxx_write_reg(priv, 0x3D, 0x04);
                }

                lgs8gxx_soft_reset(priv);
                return 0;
        }

        /* turn off auto-detect; manual settings */
        lgs8gxx_write_reg(priv, 0x7E, 0);
        if (priv->config->prod == LGS8GXX_PROD_LGS8913)
                lgs8gxx_write_reg(priv, 0xC1, 0);

        lgs8gxx_read_reg(priv, 0xC5, &t);
        t = (t & 0xE0) | 0x06;
        lgs8gxx_write_reg(priv, 0xC5, t);

        lgs8gxx_soft_reset(priv);

        return 0;
}

static int lgs8gxx_is_locked(struct lgs8gxx_state *priv, u8 *locked)
{
        int ret = 0;
        u8 t;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
                ret = lgs8gxx_read_reg(priv, 0x13, &t);
        else
                ret = lgs8gxx_read_reg(priv, 0x4B, &t);
        if (ret != 0)
                return ret;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
                *locked = ((t & 0x80) == 0x80) ? 1 : 0;
        else
                *locked = ((t & 0xC0) == 0xC0) ? 1 : 0;
        return 0;
}

/* Wait for Code Acquisition Lock */
static int lgs8gxx_wait_ca_lock(struct lgs8gxx_state *priv, u8 *locked)
{
        int ret = 0;
        u8 reg, mask, val;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                reg = 0x13;
                mask = 0x80;
                val = 0x80;
        } else {
                reg = 0x4B;
                mask = 0xC0;
                val = 0xC0;
        }

        ret = wait_reg_mask(priv, reg, mask, val, 50, 40);
        *locked = (ret == 0) ? 1 : 0;

        return 0;
}

static int lgs8gxx_is_autodetect_finished(struct lgs8gxx_state *priv,
                                          u8 *finished)
{
        int ret = 0;
        u8 reg, mask, val;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                reg = 0x1f;
                mask = 0xC0;
                val = 0x80;
        } else {
                reg = 0xA4;
                mask = 0x03;
                val = 0x01;
        }

        ret = wait_reg_mask(priv, reg, mask, val, 10, 20);
        *finished = (ret == 0) ? 1 : 0;

        return 0;
}

static int lgs8gxx_autolock_gi(struct lgs8gxx_state *priv, u8 gi, u8 cpn,
        u8 *locked)
{
        int err = 0;
        u8 ad_fini = 0;
        u8 t1, t2;

        if (gi == GI_945)
                dprintk("try GI 945\n");
        else if (gi == GI_595)
                dprintk("try GI 595\n");
        else if (gi == GI_420)
                dprintk("try GI 420\n");
        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_read_reg(priv, 0x0C, &t1);
                lgs8gxx_read_reg(priv, 0x18, &t2);
                t1 &= ~(GI_MASK);
                t1 |= gi;
                t2 &= 0xFE;
                t2 |= cpn ? 0x01 : 0x00;
                lgs8gxx_write_reg(priv, 0x0C, t1);
                lgs8gxx_write_reg(priv, 0x18, t2);
        } else {
                lgs8gxx_write_reg(priv, 0x04, gi);
        }
        lgs8gxx_soft_reset(priv);
        err = lgs8gxx_wait_ca_lock(priv, locked);
        if (err || !(*locked))
                return err;
        err = lgs8gxx_is_autodetect_finished(priv, &ad_fini);
        if (err != 0)
                return err;
        if (ad_fini) {
                dprintk("auto detect finished\n");
        } else
                *locked = 0;

        return 0;
}

static int lgs8gxx_auto_detect(struct lgs8gxx_state *priv,
                               u8 *detected_param, u8 *gi)
{
        int i, j;
        int err = 0;
        u8 locked = 0, tmp_gi;

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

        lgs8gxx_set_mode_auto(priv);
        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_write_reg(priv, 0x67, 0xAA);
                lgs8gxx_write_reg(priv, 0x6E, 0x3F);
        } else {
                /* Guard Interval */
                lgs8gxx_write_reg(priv, 0x03, 00);
        }

        for (i = 0; i < 2; i++) {
                for (j = 0; j < 2; j++) {
                        tmp_gi = GI_945;
                        err = lgs8gxx_autolock_gi(priv, GI_945, j, &locked);
                        if (err)
                                goto out;
                        if (locked)
                                goto locked;
                }
                for (j = 0; j < 2; j++) {
                        tmp_gi = GI_420;
                        err = lgs8gxx_autolock_gi(priv, GI_420, j, &locked);
                        if (err)
                                goto out;
                        if (locked)
                                goto locked;
                }
                tmp_gi = GI_595;
                err = lgs8gxx_autolock_gi(priv, GI_595, 1, &locked);
                if (err)
                        goto out;
                if (locked)
                        goto locked;
        }

locked:
        if ((err == 0) && (locked == 1)) {
                u8 t;

                if (priv->config->prod != LGS8GXX_PROD_LGS8G75) {
                        lgs8gxx_read_reg(priv, 0xA2, &t);
                        *detected_param = t;
                } else {
                        lgs8gxx_read_reg(priv, 0x1F, &t);
                        *detected_param = t & 0x3F;
                }

                if (tmp_gi == GI_945)
                        dprintk("GI 945 locked\n");
                else if (tmp_gi == GI_595)
                        dprintk("GI 595 locked\n");
                else if (tmp_gi == GI_420)
                        dprintk("GI 420 locked\n");
                *gi = tmp_gi;
        }
        if (!locked)
                err = -1;

out:
        return err;
}

static void lgs8gxx_auto_lock(struct lgs8gxx_state *priv)
{
        s8 err;
        u8 gi = 0x2;
        u8 detected_param = 0;

        err = lgs8gxx_auto_detect(priv, &detected_param, &gi);

        if (err != 0) {
                dprintk("lgs8gxx_auto_detect failed\n");
        } else
                dprintk("detected param = 0x%02X\n", detected_param);

        /* Apply detected parameters */
        if (priv->config->prod == LGS8GXX_PROD_LGS8913) {
                u8 inter_leave_len = detected_param & TIM_MASK ;
                /* Fix 8913 time interleaver detection bug */
                inter_leave_len = (inter_leave_len == TIM_MIDDLE) ? 0x60 : 0x40;
                detected_param &= CF_MASK | SC_MASK  | LGS_FEC_MASK;
                detected_param |= inter_leave_len;
        }
        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                u8 t;
                lgs8gxx_read_reg(priv, 0x19, &t);
                t &= 0x81;
                t |= detected_param << 1;
                lgs8gxx_write_reg(priv, 0x19, t);
        } else {
                lgs8gxx_write_reg(priv, 0x7D, detected_param);
                if (priv->config->prod == LGS8GXX_PROD_LGS8913)
                        lgs8gxx_write_reg(priv, 0xC0, detected_param);
        }
        /* lgs8gxx_soft_reset(priv); */

        /* Enter manual mode */
        lgs8gxx_set_mode_manual(priv);

        switch (gi) {
        case GI_945:
                priv->curr_gi = 945; break;
        case GI_595:
                priv->curr_gi = 595; break;
        case GI_420:
                priv->curr_gi = 420; break;
        default:
                priv->curr_gi = 945; break;
        }
}

static int lgs8gxx_set_mpeg_mode(struct lgs8gxx_state *priv,
        u8 serial, u8 clk_pol, u8 clk_gated)
{
        int ret = 0;
        u8 t, reg_addr;

        reg_addr = (priv->config->prod == LGS8GXX_PROD_LGS8G75) ? 0x30 : 0xC2;
        ret = lgs8gxx_read_reg(priv, reg_addr, &t);
        if (ret != 0)
                return ret;

        t &= 0xF8;
        t |= serial ? TS_SERIAL : TS_PARALLEL;
        t |= clk_pol ? TS_CLK_INVERTED : TS_CLK_NORMAL;
        t |= clk_gated ? TS_CLK_GATED : TS_CLK_FREERUN;

        ret = lgs8gxx_write_reg(priv, reg_addr, t);
        if (ret != 0)
                return ret;

        return 0;
}

/* A/D input peak-to-peak voltage range */
static int lgs8g75_set_adc_vpp(struct lgs8gxx_state *priv,
        u8 sel)
{
        u8 r26 = 0x73, r27 = 0x90;

        if (priv->config->prod != LGS8GXX_PROD_LGS8G75)
                return 0;

        r26 |= (sel & 0x01) << 7;
        r27 |= (sel & 0x02) >> 1;
        lgs8gxx_write_reg(priv, 0x26, r26);
        lgs8gxx_write_reg(priv, 0x27, r27);

        return 0;
}

/* LGS8913 demod frontend functions */

static int lgs8913_init(struct lgs8gxx_state *priv)
{
        u8 t;

        /* LGS8913 specific */
        lgs8gxx_write_reg(priv, 0xc1, 0x3);

        lgs8gxx_read_reg(priv, 0x7c, &t);
        lgs8gxx_write_reg(priv, 0x7c, (t&0x8c) | 0x3);

        /* LGS8913 specific */
        lgs8gxx_read_reg(priv, 0xc3, &t);
        lgs8gxx_write_reg(priv, 0xc3, t&0x10);


        return 0;
}

static int lgs8g75_init_data(struct lgs8gxx_state *priv)
{
        const struct firmware *fw;
        int rc;
        int i;

        rc = request_firmware(&fw, LGS8GXX_FIRMWARE, &priv->i2c->dev);
        if (rc)
                return rc;

        lgs8gxx_write_reg(priv, 0xC6, 0x40);

        lgs8gxx_write_reg(priv, 0x3D, 0x04);
        lgs8gxx_write_reg(priv, 0x39, 0x00);

        lgs8gxx_write_reg(priv, 0x3A, 0x00);
        lgs8gxx_write_reg(priv, 0x38, 0x00);
        lgs8gxx_write_reg(priv, 0x3B, 0x00);
        lgs8gxx_write_reg(priv, 0x38, 0x00);

        for (i = 0; i < fw->size; i++) {
                lgs8gxx_write_reg(priv, 0x38, 0x00);
                lgs8gxx_write_reg(priv, 0x3A, (u8)(i&0xff));
                lgs8gxx_write_reg(priv, 0x3B, (u8)(i>>8));
                lgs8gxx_write_reg(priv, 0x3C, fw->data[i]);
        }

        lgs8gxx_write_reg(priv, 0x38, 0x00);

        release_firmware(fw);
        return 0;
}

static int lgs8gxx_init(struct dvb_frontend *fe)
{
        struct lgs8gxx_state *priv =
                (struct lgs8gxx_state *)fe->demodulator_priv;
        const struct lgs8gxx_config *config = priv->config;
        u8 data = 0;
        s8 err;
        dprintk("%s\n", __func__);

        lgs8gxx_read_reg(priv, 0, &data);
        dprintk("reg 0 = 0x%02X\n", data);

        if (config->prod == LGS8GXX_PROD_LGS8G75)
                lgs8g75_set_adc_vpp(priv, config->adc_vpp);

        /* Setup MPEG output format */
        err = lgs8gxx_set_mpeg_mode(priv, config->serial_ts,
                                    config->ts_clk_pol,
                                    config->ts_clk_gated);
        if (err != 0)
                return -EIO;

        if (config->prod == LGS8GXX_PROD_LGS8913)
                lgs8913_init(priv);
        lgs8gxx_set_if_freq(priv, priv->config->if_freq);
        lgs8gxx_set_ad_mode(priv);

        return 0;
}

static void lgs8gxx_release(struct dvb_frontend *fe)
{
        struct lgs8gxx_state *state = fe->demodulator_priv;
        dprintk("%s\n", __func__);

        kfree(state);
}


static int lgs8gxx_write(struct dvb_frontend *fe, const u8 buf[], int len)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;

        if (len != 2)
                return -EINVAL;

        return lgs8gxx_write_reg(priv, buf[0], buf[1]);
}

static int lgs8gxx_set_fe(struct dvb_frontend *fe)
{
        struct dtv_frontend_properties *fe_params = &fe->dtv_property_cache;
        struct lgs8gxx_state *priv = fe->demodulator_priv;

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

        /* set frequency */
        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);
        }

        /* start auto lock */
        lgs8gxx_auto_lock(priv);

        msleep(10);

        /* TODO: get real readings from device */

        /* bandwidth */
        fe_params->bandwidth_hz = 8000000;

        fe_params->code_rate_HP = FEC_AUTO;
        fe_params->code_rate_LP = FEC_AUTO;

        fe_params->modulation = QAM_AUTO;

        /* transmission mode */
        fe_params->transmission_mode = TRANSMISSION_MODE_AUTO;

        /* guard interval */
        fe_params->guard_interval = GUARD_INTERVAL_AUTO;

        /* hierarchy */
        fe_params->hierarchy = HIERARCHY_NONE;

        return 0;
}

static
int lgs8gxx_get_tune_settings(struct dvb_frontend *fe,
                              struct dvb_frontend_tune_settings *fesettings)
{
        /* FIXME: copy from tda1004x.c */
        fesettings->min_delay_ms = 800;
        fesettings->step_size = 0;
        fesettings->max_drift = 0;
        return 0;
}

static int lgs8gxx_read_status(struct dvb_frontend *fe,
                               enum fe_status *fe_status)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;
        s8 ret;
        u8 t, locked = 0;

        dprintk("%s\n", __func__);
        *fe_status = 0;

        lgs8gxx_get_afc_phase(priv);
        lgs8gxx_is_locked(priv, &locked);
        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                if (locked)
                        *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
                                FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
                return 0;
        }

        ret = lgs8gxx_read_reg(priv, 0x4B, &t);
        if (ret != 0)
                return -EIO;

        dprintk("Reg 0x4B: 0x%02X\n", t);

        *fe_status = 0;
        if (priv->config->prod == LGS8GXX_PROD_LGS8913) {
                if ((t & 0x40) == 0x40)
                        *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER;
                if ((t & 0x80) == 0x80)
                        *fe_status |= FE_HAS_VITERBI | FE_HAS_SYNC |
                                FE_HAS_LOCK;
        } else {
                if ((t & 0x80) == 0x80)
                        *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
                                FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
        }

        /* success */
        dprintk("%s: fe_status=0x%x\n", __func__, *fe_status);
        return 0;
}

static int lgs8gxx_read_signal_agc(struct lgs8gxx_state *priv, u16 *signal)
{
        u16 v;
        u8 agc_lvl[2], cat;

        dprintk("%s()\n", __func__);
        lgs8gxx_read_reg(priv, 0x3F, &agc_lvl[0]);
        lgs8gxx_read_reg(priv, 0x3E, &agc_lvl[1]);

        v = agc_lvl[0];
        v <<= 8;
        v |= agc_lvl[1];

        dprintk("agc_lvl: 0x%04X\n", v);

        if (v < 0x100)
                cat = 0;
        else if (v < 0x190)
                cat = 5;
        else if (v < 0x2A8)
                cat = 4;
        else if (v < 0x381)
                cat = 3;
        else if (v < 0x400)
                cat = 2;
        else if (v == 0x400)
                cat = 1;
        else
                cat = 0;

        *signal = cat * 65535 / 5;

        return 0;
}

static int lgs8913_read_signal_strength(struct lgs8gxx_state *priv, u16 *signal)
{
        u8 t; s8 ret;
        s16 max_strength = 0;
        u8 str;
        u16 i, gi = priv->curr_gi;

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

        ret = lgs8gxx_read_reg(priv, 0x4B, &t);
        if (ret != 0)
                return -EIO;

        if (fake_signal_str) {
                if ((t & 0xC0) == 0xC0) {
                        dprintk("Fake signal strength\n");
                        *signal = 0x7FFF;
                } else
                        *signal = 0;
                return 0;
        }

        dprintk("gi = %d\n", gi);
        for (i = 0; i < gi; i++) {

                if ((i & 0xFF) == 0)
                        lgs8gxx_write_reg(priv, 0x84, 0x03 & (i >> 8));
                lgs8gxx_write_reg(priv, 0x83, i & 0xFF);

                lgs8gxx_read_reg(priv, 0x94, &str);
                if (max_strength < str)
                        max_strength = str;
        }

        *signal = max_strength;
        dprintk("%s: signal=0x%02X\n", __func__, *signal);

        lgs8gxx_read_reg(priv, 0x95, &t);
        dprintk("%s: AVG Noise=0x%02X\n", __func__, t);

        return 0;
}

static int lgs8g75_read_signal_strength(struct lgs8gxx_state *priv, u16 *signal)
{
        u8 t;
        s16 v = 0;

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

        lgs8gxx_read_reg(priv, 0xB1, &t);
        v |= t;
        v <<= 8;
        lgs8gxx_read_reg(priv, 0xB0, &t);
        v |= t;

        *signal = v;
        dprintk("%s: signal=0x%02X\n", __func__, *signal);

        return 0;
}

static int lgs8gxx_read_signal_strength(struct dvb_frontend *fe, u16 *signal)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;

        if (priv->config->prod == LGS8GXX_PROD_LGS8913)
                return lgs8913_read_signal_strength(priv, signal);
        else if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
                return lgs8g75_read_signal_strength(priv, signal);
        else
                return lgs8gxx_read_signal_agc(priv, signal);
}

static int lgs8gxx_read_snr(struct dvb_frontend *fe, u16 *snr)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;
        u8 t;
        *snr = 0;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
                lgs8gxx_read_reg(priv, 0x34, &t);
        else
                lgs8gxx_read_reg(priv, 0x95, &t);
        dprintk("AVG Noise=0x%02X\n", t);
        *snr = 256 - t;
        *snr <<= 8;
        dprintk("snr=0x%x\n", *snr);

        return 0;
}

static int lgs8gxx_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
{
        *ucblocks = 0;
        dprintk("%s: ucblocks=0x%x\n", __func__, *ucblocks);
        return 0;
}

static void packet_counter_start(struct lgs8gxx_state *priv)
{
        u8 orig, t;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_read_reg(priv, 0x30, &orig);
                orig &= 0xE7;
                t = orig | 0x10;
                lgs8gxx_write_reg(priv, 0x30, t);
                t = orig | 0x18;
                lgs8gxx_write_reg(priv, 0x30, t);
                t = orig | 0x10;
                lgs8gxx_write_reg(priv, 0x30, t);
        } else {
                lgs8gxx_write_reg(priv, 0xC6, 0x01);
                lgs8gxx_write_reg(priv, 0xC6, 0x41);
                lgs8gxx_write_reg(priv, 0xC6, 0x01);
        }
}

static void packet_counter_stop(struct lgs8gxx_state *priv)
{
        u8 t;

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                lgs8gxx_read_reg(priv, 0x30, &t);
                t &= 0xE7;
                lgs8gxx_write_reg(priv, 0x30, t);
        } else {
                lgs8gxx_write_reg(priv, 0xC6, 0x81);
        }
}

static int lgs8gxx_read_ber(struct dvb_frontend *fe, u32 *ber)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;
        u8 reg_err, reg_total, t;
        u32 total_cnt = 0, err_cnt = 0;
        int i;

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

        packet_counter_start(priv);
        msleep(200);
        packet_counter_stop(priv);

        if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
                reg_total = 0x28; reg_err = 0x2C;
        } else {
                reg_total = 0xD0; reg_err = 0xD4;
        }

        for (i = 0; i < 4; i++) {
                total_cnt <<= 8;
                lgs8gxx_read_reg(priv, reg_total+3-i, &t);
                total_cnt |= t;
        }
        for (i = 0; i < 4; i++) {
                err_cnt <<= 8;
                lgs8gxx_read_reg(priv, reg_err+3-i, &t);
                err_cnt |= t;
        }
        dprintk("error=%d total=%d\n", err_cnt, total_cnt);

        if (total_cnt == 0)
                *ber = 0;
        else
                *ber = err_cnt * 100 / total_cnt;

        dprintk("%s: ber=0x%x\n", __func__, *ber);
        return 0;
}

static int lgs8gxx_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
{
        struct lgs8gxx_state *priv = fe->demodulator_priv;

        if (priv->config->tuner_address == 0)
                return 0;
        if (enable) {
                u8 v = 0x80 | priv->config->tuner_address;
                return lgs8gxx_write_reg(priv, 0x01, v);
        }
        return lgs8gxx_write_reg(priv, 0x01, 0);
}

static const struct dvb_frontend_ops lgs8gxx_ops = {
        .delsys = { SYS_DTMB },
        .info = {
                .name = "Legend Silicon LGS8913/LGS8GXX DMB-TH",
                .frequency_min_hz = 474 * MHz,
                .frequency_max_hz = 858 * MHz,
                .frequency_stepsize_hz = 10 * kHz,
                .caps =
                        FE_CAN_FEC_AUTO |
                        FE_CAN_QAM_AUTO |
                        FE_CAN_TRANSMISSION_MODE_AUTO |
                        FE_CAN_GUARD_INTERVAL_AUTO
        },

        .release = lgs8gxx_release,

        .init = lgs8gxx_init,
        .write = lgs8gxx_write,
        .i2c_gate_ctrl = lgs8gxx_i2c_gate_ctrl,

        .set_frontend = lgs8gxx_set_fe,
        .get_tune_settings = lgs8gxx_get_tune_settings,

        .read_status = lgs8gxx_read_status,
        .read_ber = lgs8gxx_read_ber,
        .read_signal_strength = lgs8gxx_read_signal_strength,
        .read_snr = lgs8gxx_read_snr,
        .read_ucblocks = lgs8gxx_read_ucblocks,
};

struct dvb_frontend *lgs8gxx_attach(const struct lgs8gxx_config *config,
        struct i2c_adapter *i2c)
{
        struct lgs8gxx_state *priv = NULL;
        u8 data = 0;

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

        if (config == NULL || i2c == NULL)
                return NULL;

        priv = kzalloc_obj(struct lgs8gxx_state);
        if (priv == NULL)
                goto error_out;

        priv->config = config;
        priv->i2c = i2c;

        /* check if the demod is there */
        if (lgs8gxx_read_reg(priv, 0, &data) != 0) {
                dprintk("%s lgs8gxx not found at i2c addr 0x%02X\n",
                        __func__, priv->config->demod_address);
                goto error_out;
        }

        lgs8gxx_read_reg(priv, 1, &data);

        memcpy(&priv->frontend.ops, &lgs8gxx_ops,
               sizeof(struct dvb_frontend_ops));
        priv->frontend.demodulator_priv = priv;

        if (config->prod == LGS8GXX_PROD_LGS8G75)
                lgs8g75_init_data(priv);

        return &priv->frontend;

error_out:
        dprintk("%s() error_out\n", __func__);
        kfree(priv);
        return NULL;

}
EXPORT_SYMBOL_GPL(lgs8gxx_attach);

MODULE_DESCRIPTION("Legend Silicon LGS8913/LGS8GXX DMB-TH demodulator driver");
MODULE_AUTHOR("David T. L. Wong <davidtlwong@gmail.com>");
MODULE_LICENSE("GPL");
MODULE_FIRMWARE(LGS8GXX_FIRMWARE);